IMHO it is definetely a bug! Which module is faulty I can not tell. But odds are...
Yeah, now I replaced all solid fills by a very dense hatch and removed all features...
Further Investigation taught me that the arrows drawn by the 'dimensions' menu aparrently...
Apparently solid fills are causing this problem. If there is just one solid fill...
Splines: solid fill in additional layers
Errm, I thought I did report this as a Bug by writing this. What else do I need to...
Layer sort order in modify -> attributes
Thank you for the input on this, which made me open feature request 153 on this issue....