Well, actually it is easiest if you get them straight in camera. Those who use PhotoPaint and have seen PSP or LightRoom in action can develop Horizon Correction envy. It is actually quite easy to correct horizons in PhotoPaint without scripts or complex calculations.
I have put a tutorial (1.4 MB Video) HERE
I hope it is useful.
Rikk Flohr said: I have put a tutorial (1.4 MB Video) HERE
If you want the video, email me through my contact info on Coreldraw.com and I will send you the swf file.