I really like this currently, I downloaded it last night and loaded up some spriting tutorials. I made an okay sprite I guess, haha.
There are a few things I think should be changed:
Firstly, if you look at the "File" tab, you have it so that it is "FIle" I know it's only a minor spelling mistake, I thought I'd point it out.
another thing is that last night I saved some work, then today when I loaded it up, there were a few grey pixles that had added themselves. It wasn't anything too bad, but it was still a bit meh xD
Also, the rubber icon, when you use it looks weird, as if the image hasn't been put in proparly. I tried getting an image of it, but it wouldn't show up in screen shots. Could be a problem with my computer maybe...
I have to say, the biggest hinderence so far has been the lack of the select tool, it means I have to completely copy out a sprite I've made before if I want it copied... I think you're working on that right? When that is added I will love this program! :P
Everything about this so far is good, I'm glad you made something so great!
I hope you continue to work on it and make it better than it already is!
Edit: Also, I must say, I Find it rather annoying that the sprite sheet has to be a multiple of 8... I'm sure there is a reason that it has to be a multiple of 8, but I work on single sprites before moving it into a bigger sprite sheet, this is made hard when I have to compensate for multiples of 8 xD