When I tried to watch a Blue-ray movie on Sat. Cyberlink PDVD (7.3) forced me to download the latest rev of their player.  Later when we went to watch a H.264 recording I discovered that the PDVD H.264 decoder wasn't available anymore (found out later that the VC-1 wasn't either, but it won't be missed).  Fortunately I keep copies of each update so I was able get back to the previous revision, and take a copy of the VideoFilter folder (C:\Program Files\CyberLink\PowerDVD\VideoFilter) before installing the 5105 update, running regsvr32 on CL264dec.ax got everything working the way I want again.

What I find really upsetting about it all, is the shifty way that Cyberlink took away functionality from a product that I'd paid for (actually the second time this happened with the same product) through a mandatory update.  Cyberlink you suck!