I ran into this problem several times. This might be no
great help, but I only have those sort of problems with older
PCS-Versions and models with geometrical errors. (I found out
myself too, that the dos-converter sometimes mangaged to do the
cob-file anyway, however I didn't get thruster running when
using the dos-converter). With the dos-converter you have virtually
no chance creating a better model with turrets, debris and LOD, so
better forget it.
The newer PCS-Versions normally gaved me an error-message :
"Stack overflow protections was engaged..." or something.
I really hated that sentence with the time.
However, I never really understood what this message should
tell me. Most of the models I had this problems were bad extractions
from other games which doubled faces etc, never had those
problems with self-created models though.
Try the following :
Go to the SCP-forum, there must be a special PCS-version for
High-Poly-Ships
Delete all subobjects and Lod's, maybe the failure is in one of
the subobjects. Try piece for piece, which one contains the error.
Make the model bigger (really, this worked for me two or three
times). You can set the PCS-scaling factor down then. Seems like
this stack-overflow thing is a problem where too many Polygons are
to near to each other.
Might be nothing, but still worth a try.
Good luck
