Thanks to the generosity of Adobe I received a time-limited licence for CS6 Production Premium on OS X to test and debug my plugins. The response to my inquiry was immediate, with no additional questions asked. I admit I am totally impressed with their reaction. Kudos, guys!
I was able to fix a really nasty render bug that made the Feathered Crop almost unusable with the latest version of Premiere, what a few users pointed out to me, some in a kind manner, others not so much.
As far as I was able to test it, the version 1.2.1 of the Feathered Crop should be production ready. Download it here and enjoy:Feathered Crop CS6 OS X v1.2.1 (2215 downloads)
There might still be a few issues with displaying when the paused resolution is less than full, which I will try to address in the future, but if you find out that there are still some big problems, please let me know. And yes, test the plugins within your workflow before you start applying them en masse.