Historical Aged Trial Balance - Microsoft Dynamics GP Hangs

It has been quite some time that the Historical Aged Trial Balance Report seems to process for ever not completing. Decided to get Profession Microsoft support and here is the out come:

• The report was tried to run for a single vendor - the symptons contined.
• Monitoring on the Profiler, the process was active and no idication of any exceptions.
• sp_who2 did not indicate any spid in waiting.
• Dynamics GP Process monitor did not show any other hanging jobs.
• The poking around for any signs of problem continued and it was noticed that one of the report options was named "+" - Would this cause a problem ? - The report option set was deleted.
• Another report was started to add to the process monitory queue, and then attempt was made to suspend and kill the two processes, at this time got a message "Unable to update temp table". Got passed the mesasged and cleared the processes.
• Cleared the C: Drive to ensure there is at atleast a Gig of space free.
• Started the run the report for one vendor, it worked, the tried to couple vendors, it worked.
• Decided it was time to run the the report for the entire set, and was prepared for long haul wait - finally after about an hour the report completed.

So what was the problem ?

1. "+" Plus sign on report Options caused the report to hang ?
2. Low Disk Space on C: Drive a reason for temp table to crash letting the report to hang for ever ?
3. Was it a question of lack of patience to wait for an hour for the report to complete ?
4. Was it a stuck process which was invisible at the process monitor, which eventually got cleared when the subsequent jobs were cleared with an error message ?

Waiting for analysis.