I've talked to the OnTime manager and author, and he speculates that Vault is not returning the list of groups correctly with Privileges. Here is his quote:

http://pastebin.com/sPVqDY2k

OnTime manager/author doesn't seem to understand the difference between instantiating with a pre-sized array and not. This has nothing to do with the contents of the array. For reference on why NOT to do this see: http://stackoverflow.com/questions/174093/toarraynew-myclass0-or-toarraynew-myclassmylist-size

If Privs returns an empty group array, then no groups were loaded in the manager. This is something you'll want to discuss with the Privileges author.