I am 90% sure that that is wrong. Other scenes, built-in scenes, call reserveFaceImages in their create, and that works. There's also Scene_File which calls reserveCharacter in its create. So there must be a way that works without putting it in Scene_Boot.
For a custom window skin, yeah, Scene_Boot makes sense; but for characters, I don't believe that's the right answer.
For a custom window skin, yeah, Scene_Boot makes sense; but for characters, I don't believe that's the right answer.
Personally, putting the reserve method in the create function never worked for me. And yes, I too have seen built-in scenes doing it this way, but never worked for me. Why not just do it in the Scene_Boot? It will save you a lot of trouble.
I use Scene_Boot for all costum images, from menu Icons to large detailed pictures. They all load erroneously otherwise.