Installing PlayFLV alone was NOT sufficient in my case. I also needed to install the FLV-Splitter from
here ! (
important: the Splitter in this download works, there are others out there which didn't work for me !)
-level20peon
EDIT: OK, seems like PlayFLV installs the FLV-Splitter, but the version differs (1.0.0.1 is installed, 1.0.0.4 is the one out of my download). Both versions play FLV if I add them in Video-Postprocessing BUT both make MediaPortal crash if I play anything else than .flv. I will have to investigate this and get back when I have news.
@userjan: I tried your solution but there is no "FLV-Player" in the "external players" section of my MP config (RC1).