Speed of Scribus a Qt(4.8) app on different PC's

Hello all…
Scribus (www.scribus.net) is a great program for layout and text… it can easily used as Word Processor. It even has great PDF export functions… It is a Qt 4.8 program.

There are a few limitations so far. Right click seems not to work, so you have to use the menu bar commands. Drawing text- and picture frames is very slow on some systems!

So I wonder why the speed differs so much on different Computer systems. I suspect it has something to do with 2d acceleration!?

Pentium 4 2 core system with 2400MHz is not usable… the teapot demo spins with 160fps! Graphic card works… If I try to draw a text frame it is drawing and deleting the lines which makes Scribus unusable!
Pentium4 2 core laptop with 1300MHz is with no problems usable… teapot spins here 60fps… Graphic card works… Drawing frames is slow but acceptable!
Pentium i5 system is usable… no wonder why… but vesa mode…

What to do to get more speed? How to disable acceleration on the P4? Maybe it will work faster then? How to examine the speed differences? Any idea? How to get Qt draw the frames faster?