I'm guessing this bug has stopped anyone else looking at it, shame really, without feedback it makes improving it and getting it right pretty tough.
Bugs usually do that :)
But hey, at least you noticed that it has one because ppl *did* take a look. And once the bug is fixed, more feedback will follow I'm sure.
One thing to note is that although this app is cool and very useful for texture tweaking / generating, it doesn't have anything I can't do with Photoshops layers and effects? Yes, I know, PS cost a lot... but for ppl who do have it (through work or have bought it) it's not really that tempting to switch using app like yours - it's just additional cost and you have to learn to use yet another program.
But I'm sure that something like this would be useful for many game makers here, especially if they don't have Photoshop.