Yes, the render.library did the trick Thanks... The Errormessage allways said, that guigfx.library is missing.... but after installing render.library everthing is working....
That's because guigfx needs render but NetSurf only needs guigfx, it doesn't know about render.
but extreamly slow! 3.7 is 4 times faster....
The source code is available if somebody actually wants to try fixing this issue rather than just whinging about it on a forum.
As it happens, it appears that I've used -m68020 everywhere and although I don't recall changing this, at some point in the past I'm fairly sure I used one of the more compatible options.