I seem to be having some difficulties with this tutorial. I use the latest version of GIMP so that might be some of the problem, but after I have made all of the mountains and exported them to brush form, they come out much smaller and sort of... "smushed". It looks a little like someone took the 400 x 400 mountain images and made them smaller using Paint; they are incredibly pixelated and do not look at all how they look in the guide.

It's a little frustrating, since otherwise I haven't had any problems, but this is an important step I think. I went over the instructions to make sure I hadn't made a silly mistake somewhere, and I don't see anywhere where I differed. It's quite perplexing, does anybody know what might be happening?