The Map Problem

Ok, i am hard-working on this one...
The problem is due to my use of a very simple "projection", actually too simple! This, of course, introduces a "distortion" which become bigger as latitude increases or decreases. The solution? I am still studying the problem, but it might seems to be to implement libproj4 in FreeTrack and select a suitable map projection (proably an equal-area cylindrical projection?)...