It seems to me that the Pixel Bender Toolkit is an unloved piece of software. I Sunday afternoon on a project, pulling my hair out trying to figure out why my filters where behaving oddly.
This evening, I've realised that the toolkit always to seems to save the PBJ and PBK files to the Adobe/Pixel Bender directory under my documents folder. Even if I open a PBK file from another directory, toolkit saves in its default directory. It's a proper return to the 1980's where I have to reset the directory path whenever I save or export a filter.
While I'm at it, can we have better Pixel Bender support in Flash Player? Arrays and functions would be nice.
Please post your feature requests on the Pixel Bender Wishlist thread at http://forums.adobe.com/thread/787658?tstart=0. As for the Flash Player request, you will need to direct this request to the Flash Player team. I suggest that you post this request on the Flash Player forum. Best of luck.