ERROR: G_ParseSpawnVars: found 5 when expecting {
The cause for this error is simply that the homepath variable has been changed in newer SVN tremdeds.
As for your "nobuild" problem, it seems that P-G QVM with Amanieu's serverside demo patch does not work with any tremded, be it FSM-Trem or MG Semipure. My advice to you is to simply use a stock P-G QVM, without Amanieu's patch, as this works even with tjw's tremded.
- Yarou