hello, thanks for the responses
1. sorry, i was mistaken. the program doesn't crash - it freezes, particularly on larger drawings. it does unfreeze if you wait long enough, so just a cpu/memory limitation/problem or somethin.
3. 16 seems to be enough
8. i see. i'd also like to add a related problem i've noticed: the preview does not update until you move far enough. it seems to snap at a certain number of pixels, and it scales the bigger the canvas is.