There is a release of qbo.CoreWeb that causes errors with main menus and some popup windows.
The cause of the error is a mismatch between MooTools core and clientcide files.
To fix this issue, you can either:
The latest release in qbo.CoreWeb > Web Tier > qbo.WebRoot > Libraries > MooTools (as of this post) is:
The Standard skin has been modified to use these latest MooTools files. I have unit tested for the bugs mentioned above, and I will be regression testing in the next few days.
Note that I built the MooTools libraries from: