pvrx2 works for me via remote desktop from an xp pc to the vista server. the only problem is that you need to log the server in again when you have finished which is a royal PITA.
I stayed again from VNC during my new server build in case it may have interfered with the video playback (probably a baseless notion) but on my previous server I used ultra VNC sucessfully for a long time. Inf fact, I may just go away and install it again.
Silverstone LC17 Case,
ASUS P5Q, Intel E7200, 4GB RAM
Blackgold DVB-T2, ATI 7750, Windows 7 64-bit
SAF codec pack,Sony 40" Z5500