Well I'm using AE CS4 with just about ALL of the Trapcodes and Red Giants Plug-ins.
Upon copying the entire contents of the folder to the Fusion folder, I noticed that some of the plug-ins crash Fusion. The perpetrators seem to be the ORIGINAL AE plugins located in "Adobe\Adobe After Effects CS4\Support Files\Plug-ins\Effects" (ie ones that directly come from Adobe). The CycoreFX, Foundry, and Synthetic Aperture plug-ins work fine, but it's the plug-ins that aren't in a folder that are causing me grief.
I would go through, plug-in by plug-in, to see which ones worked and which ones didn't...but I'm sure someone has already done the footwork.
So...what plug-in from the ""Adobe\Adobe After Effects CS4\Support Files\Plug-ins\Effects"" folder work in Fusion?