Hi-

I've done this on two occasions. However, I wouldn't say it was easy either time.

The big items to watch out for are setting up the __autoload function. There can be only one Autoload, and this threw a big monkey wrench at me once.

Second is the error handling. Qcubed makes extensive use of custom error handlers in the Qcontrols, and I found this to be difficult to work around.

I'd suggest taking a close look at QDrupal, a drupal module I wrote that integrated Qcubed (and Qcodo) into the Drupal CMS. http://drupal.org/project/qdrupal

Mike