tflak
Veteran
This is very messy, Larry.... with each conversion you loose quality. AVHCD to ProRes to h264 to flv. To edit in FCP you cannot skip the ProRes part but you can either drop the h264 or the flv part and since flv is now old technology you should drop that. So export in h264 and upload them to your site, your flash players should be able to play them (all new flash players play h264 files with .mp4 extension). If not, try changing the extension into .flv . But stay away from flv encoding if you want best possible quality.
Right you are except for one small part. You cannot simply change the file extension to FLV. They are two completely different animals.
FYI - there is a specialized version of H.264 for Flash that uses the F4V extension. But this is only used if you need to include something like cue points. And, once again, it's not a simple matter of changing file extensions; it's encoded differently.