I'll start with some of the stuff I really liked. The art is lovely, the voice acting was a nice touch (though I do have thoughts), and the maps clearly have lots of time and love put into them. There are a lot of hints at mysteries in the story, and while the demo doesn't go too in-depth it does have some good hooks. I also liked that you had quite a few little details and minigame hidden around the starting village to teach players to explore without coming out and going "look around you fools!" in a message box. And I was honestly disappointed when the demo ended because I wanted to keep playing and see how Thomas would fit into my battle style.
That said, there were things that I think need more work. I found the game stuttering and dropping below 20FPS on certain outside maps (though it usually ran fine indoors and on other outdoor maps), so I don't know what is going on but it was a rough introduction to the game when I was slowly walking around the first map. I tried turning off the screen effects in the Options menu, but that didn't seem to really affect the FPS unfortunately. I'm guessing it's related to either parallel processes or a plugin, so you may want to double-check the starting map to see if there's something odd there that is used on other maps too.
I do like that you have an icon when you approach an item that can be interacted with, but since you have to be right next to the event and facing it it's easy to miss something unless you're rubbing your face against everything. I think there's a balance you could find between the current method and having an icon fully visible at all times. Maybe the icon appears when you're within 3 tiles of the event, or opening the map will also mark interactable spots. Two spots where I really think this issue is a big problem is in item shops and when finding plants in the wild. The first time I played I didn't even realize that the item shop had Potions and Magic Water for sale! The shopkeeper didn't have them as an option in his menu, so you could only buy those if you went to the back of the shop and interacted with the bottles on the table, which I thought were just decorations since the table right in front of the door didn't have anything you could click on. In a situation like that, I think it would be best if the shop's for-sale items were clearly laid out or always marked with an icon so that players can easily tell what they could buy. And when it come to finding plants in the wild, I found that some of the grasses were used as normal decorations under trees so I would think there was another I could collect but it turned out I couldn't reach it. Collectable plants could really use icons that appear when the player is a few tiles away, or some subtle sparkles to draw the player's eye.
I love minigames and crafting systems, so imagine my delight when I realized this game has quite a few! Unfortunately it felt like some of them were more of an afterthought in this demo, and it may have been better to leave them out until a later demo or the full release. I only found the Fishing Rod during my 3rd playthrough (didn't realize Senersis' house was down the previously closed road), and while I liked it I didn't really need to eat any fish while playing. The card matching minigame I did enjoy, but I didn't realize that I needed to use my mouse for it at first so I was just clicking on my keys and wondering why nothing was happening. I think the music minigame was the weakest one I played, for two reasons: first, I play with the sound off because I get headaches from game sounds easily, and second, it was a very long introduction to the minigame. The first point isn't something you can really fix, just have to keep in mind that not everyone can or will hear musical cues, but I think the second one could be easily fixed. Shorten that first music minigame by half, and that should help players learn how the minigame works without it feeling overwhelming.
The crafting system really disappointed me. I was excited when I first got a recipe thanks to a side quest, but that was the only one I found. Considering the number of plants I found, I know there are more recipes in the game but I was never poisoned in battle so being able to make a few Antidotes didn't really help. Perhaps later in the game it will be useful, but for an introduction to the crafting system it felt like the game was telling me "here is a system that you won't be using"... I think if you're going to have crafting, then giving a Potion recipe early may be better. I didn't really use items in battle at all since HP and MP seemed to be healed after most fights, but a Potion would be a lot more helpful early in the game than an Antidote.
Speaking of using items in battles, I think battles were the weakest point in this entire demo. They were
fine, but compared to the rest of the demo they didn't feel as polished. The normal enemies were easy enough to defeat just with Ennea using magic and Aehlevander using his normal attack, so I rarely used Aehlevander's support spells. The fact that they could only target one party member at a time was definitely another reason I didn't use them often, since by the time I had buffed both of them the battle was usually over. So imagine my surprise when I went through every fight before the wolf boss battle, and the boss fight kicked my butt almost instantly! I understand boss fights should be challenging, but its Multiscratch attack could do more damage than Ennea could stand, so early in the battle she would be dead and I'd need to revive her. I did all I could, buffing their defense and attacks, using the strongest spells I had access to, using their combo skills, and I still got a game over. It ended up that I needed to leave the map so all the enemies respawned so I could fight them all again and level up more before I stood a chance, and even then Ennea died a few times. I honestly thought I wasn't supposed to win that fight the first time, just because of how much HP the boss had and how deadly its attacks were. A challenging boss battle is fine, but I think the Multscratch attack needs tweaked so that it's not a one-hit KO for Ennea, since she is the main damage dealer.
The skills all worked, but I feel like I must've been missing something when using them. The Fire spell was strong so I used it often, but for some reason the state that is applied made the enemy resistant to fire attacks? For normal enemies it didn't really matter since I could still kill them with normal attacks after that first spell, but I expected enemies to be weaker to flames when on fire or maybe take more damage from the nature spells. It would have been cool if the different types of magic had an effect that could boost or weaken other types of magic, so players would need to think before casting spells willy-nilly. Aehlevander only gained one debuffing skill while I played, Slow, so I didn't see how debuffs could help in battles much but I do think him buffing the party one turn and then debuffing the enemies the next turn could really turn the tides in harder battles. Most of the normal enemies seemed to lack weaknesses to any elements (besides the foxes, who seemed resistant to nature spells), so I didn't really have to plan out my attacks beyond "hit hard and hit fast". If elemental weaknesses will be important later in the game, it would be good to have some enemies that clearly were weak to Ennea's nature spells just so players get it into their head that they should think before clicking a skill.
There were a few other bugs and oddities. Since I did play at least the beginning of v1.0, v1.1, and v1.2, I'll mark the errors with the version I found them in just in case you've already fixed some of them and I missed it:
- Why are the blue elves called just the blue elves, compared to luminous or forest elves?
- [v1.0] Opening a map with 'tab' is a cool effect, but you may want to turn off mouse-control when it's up since it looks like you're clicking one spot on the map but it's actually just moving you on the map
- [v1.0] Can use both Cat and Dog Food from the menu (they're listed as Battle Items), just deleting them from existence
- It's cute that feeding cats and dogs gives a boost, but it looks like they can't exist together? May be kinder on players to warn them that feeding one will remove the other regen. And sleeping and walking around wipes it out too, so it doesn't really seem worthwhile
- The floor in the castle is incredibly shiny since items on the wall are reflected, which makes it odd that the people don't have reflections
- Balloons are very high above the sprites' heads, consider using a plugin to move them closer to the tops of the heads
- [v1.0] The music minigame is neat, but you should cover what keys will possibly be included in the game before it starts. The sudden 'W's and 'Q's threw me off. Also it really could do with some visuals as well. Players can hear the good/bad SEs, but a little pop of cheery green would add more visual interest while playing
- [v1.1] A minor thing, but changing the unicorn's hitbox to be wider so you can interact with him face-to-face instead of getting right next to his body would look nice
- The part of town to the left of the castle (with NPC Martin de Visee) does not have a compass
- Door above Martin de Visee is set to 'above character'. Same with the house north of that one. Oh, all the houses on this map suffer from the door problem

- [v1.1] The card matching game is a neat idea, but it requires the use of the mouse. Make sure the player knows that when going into the minigame! Would also be good to have a counter so players know how many chances they have left
- [v1.1] The statue that gives a boost in the forest to the right of the castle has an 'undefined' message

- [v1.1] I turned Battle Voices off in the settings, but they still play if I have Voice Volume on
- [v1.1] While I do like knowing the enemy's sight range, the bright red is a bit distracting. Maybe tone it down a bit, or have an option to turn it off?
- [v1.2] The fish item descriptions go out of the screen
- [v1.2] Senersis is mentioned by the King's assistant, but he isn't mentioned again so it's easy to miss visiting his house. Instead of a message saying not to go that way, have Ennea mention Senersis lives that way, but she needs to visit her father first before saying goodbye
- [v1.2] Reading Midgar's letter on his bed ends with Ennea's picture flipping in the middle of the screen randomly
- [v1.2] Trying to use the Scroll of Healing on Ennea has an 'undefined' message
- Can be selected in battle: Fishing Rod, Midgar's Letter, Pet Foods, Experience Orb, Note III. In fact, a number of non-battle items are marked as usable in battle
- While I understand why you set it up this way, Aehlevander congratulates Ennea for using her magic even if she doesn't attack the first turn in the tutorial battle. May want a check in there to make sure Ennea has damaged an enemy first
- On the map with the tutorial battle, Ennea can go under the grass and vines on the left side of the river

- On that same map, fishing bubbles appear in the upper left corner of the screen, far from the water
- Treasure chests stay on the map & compass even after they've been opened, maybe have them change to an open icon instead
- The fishing minigames in the forest don't have the "want to fish?" message, it just has the yes/no choice. Could have a Fish/Not now choice instead
- Interacting the the dead wolf makes it disappear, but the tile is still blocked by its body
- Can walk on the stone statue in Renevia village, near the well
- At the farm shop, items with 'undefined' descriptions: Red Pepper, Tomato, Peas, Broccoli, Garlic, Pumpkin
- Can't walk through some of the moving yellow flowers near the cemetery

- The ground herb plant behind the gravestones gives a Potion, not a plant