I did two projects on Infopath2007 . I got the chance to work on high level info path object model and have played around one year on infopath surface.
I would like to post one of the simple screenshot which explain the validation of the form.
After reviewing related docs Supervisor group should change task status based upon errors.
In this screen shot based on Minor and Major errors(s) user should select the proper approval choice (COMPLETED, COVERWRAP, INVALIDXEMID, REJECTED, ALREADYAPPROVED, AWC, NOTSTARTED, FAILED and SUBMITTED etc).
These three controls would depend upon each other. I implemented rules to select proper options based upon severity else show error message on the form.