[stalker96]

Make a batch. OSSRecording posted some ffmpeg commands on page 2 at the end of the script, and they're roughly the same as mine, a twist the output container should be mkv. Use mkbtoolnix (mmg), drop the final file in it and in Global tab enable splitting, just enter the time from where the show starts and it will make a split with the frozen part and one with the actual show. Through this method, the silence and fast-forwarding get fixed by ffmpeg with -async 1, that's the whole secret.

So far there's no other way, and probably will never be since what we are asking isn't normal usage... and I doubt Adobe will allow anyone to make such apps for the flv file format.