Hello. I'm fresh Flash Catalyst 5.5 user and I suppose I do something wrong. I tried to open .fla template simply by double-clicking it, but it is not recognized. Then I tried to rightclick on it and choose 'open file with', but when I choose FC 5.5 it just opens as new, empty file. I search whole lot of forums and it seems no one but me had ever problem like this. I hope in this case I'm just stupid and it's something obvious, i.e. FC doesn't read .fla files, and it's not my templates what are corrupted.
Unfortunately Flash Catalyst does not support flas. It will import swfs and use them just fine. Flash Catalyst is really the design tool for Flash Builder.
Hope this helps.
Thanks for clearing out, it seems I just have to build my templates in .swf's. Cheers!