I just made a trial installation of this, finally, and found some minor caveats.
First, the category list numbers need to start from 0 and be consecutive numbers, which wasn't entirely clear, should be in the description. Or even better, why not just sort by the number and do the loop on the number of rows returned?
Also, the check for if the user is in the right group isn't entirely correct. If the group chosen is first on the list, php returns a false value (position 0). Just change the following:
if (!strpos($user['U_Groups'],$dlgroup)) {
to this, in all pages:
if (strpos($user['U_Groups'],$dlgroup) === false) {
It was also a bit of a pain that the configuration strings weren't the same in all files, it would have made it so much easier to do a search and replace. =]
I think it might be a good idea to add the updated instructions to the main package in the first post of this thread.