Parallax Mapping problem

Well I've started learning how to do parallax mapping. I already managed to make the ground layers. Now I need trees. I've tried to save trees as brush but the only thing I manage to accomplish is this http://gyazo.com/819d64e24d4dc0f4733ab689ce197541

Is there a way to cut the white things of it? And why does it look so low-quality as a copied it with full high quality.

This is how I saved the tree as brush http://gyazo.com/f975d9bc759124251a4cb87d3f177e09

(I'm using GIMP btw)

I'm learning it from this tutorial, he shows everything right, except the trees, he uses the trees he already had saved. I don't know xd



The treepart of the video is around 7:53. Maybe you can take a look yourself. I don't get what he does.

(TURN ANNOTATIONS ON)

I do this by opening the tileset PNG for trees in gimp or whatnot, (it already has a transparent background), then just select the tree you want, copy it, and then paste it

in to your map.

If you do it this way then you can make the top half of the tree passable, by placing the top half of it on to a new layer. (very important) ;)

Remember to set up a grid of 31pixels subdivisions 1 ;)

When you input your parallax map in to RPGM, you will need to set which tiles your player can walk on, and which he cant. So best to make sure you're using the grid

and multiple layers (trees/pars)

If you want more help, I'll be happy to lend a hand, just add me to skype contacts, details in my profile.