yes back up your whole gbpvr folder (i know you rpobably wont need it but its the safest way i have found cause you forget all the little things you have changed that you forgot about)
your symptoms sounds very similar to mine the icon would flash on for a second then be gone but mine played just very jerky though unwatchable
once i did the repair install it was all ok again
Sorted now!
Thank you for your input guys, but in the end this problem with Putridvideo was solved by changing the deinterlacing type from 'Smart' to 'Automatic'.
I did read some threads about this setting causing problems, but as my GBPVR was working well for a while with 'Smart' enabled, I assumed it was a bug with the trial version.
Anyway I can view all recordings now, both mpg & dvr-ms
Not sure what the diff is between Smart & automatic - will have to look it up.
Pob