I've always heard great things about this game (I come from the Raptor camp)

So I decided to give it a spin. It actually looks very promising, but there seems to be a slight glitch: the game (sfx and graphics) actually slows to a crawl when clouds appear on screen (running on 9k cycles dosbox)... once the clouds leave, however, the game speeds up to an insane speed. Any ideas why this is happening or if they is a way to disable the clouds altogether? Thanks.