Roger pointed me towards the solution. Turns out this is a bug of some kiind in blitz' tweening. He pointed me towards this article:
http://www.blitzcoder.com/cgi-bin/articles/show_article.pl?f=gamemorduun03212002.html
As an alternative way to handle FPS limiting. It works like a charm, more efficient, plus fixes all these 'ghosting' type problems with hidden entities.
http://www.blitzcoder.com/cgi-bin/articles/show_article.pl?f=gamemorduun03212002.html
As an alternative way to handle FPS limiting. It works like a charm, more efficient, plus fixes all these 'ghosting' type problems with hidden entities.