Skore - Keep up the good work man. Just downloaded and installed the RC2p on J1.5.11. Had to do 2 things to make it work without errors:

a. disable warnings in php.ini (this was to get rid of the "acctexp.class.php on line 735" error, something about an array, it was posted earlier in this thread. hopefully this issue will get resolved so that i can undo the php.ini hack.

b. uninstalled CB1.1, it was causing duplicate emails and registration messages on the "checkout" page. i am guessing the latest version of CB would fix this issue but i haven't installed & tested it yet.

c. install the updated plugin that Jake posted on the valanx.org home page. very speedy response to the J1.5.11 security update!