I would say that it is definitely a limitation of Excel. First of all, I bet the report is trying to export all the info to Sheet1 instead of spreading it evenly amongst the available sheets. Second of all, Excel only allows like 65,000 rows of data. Lastly, I don't think your NText values can fit in an Excel Column.
Try pulling out the NText values off your report and (in test mode still) exporting to Excel then. Does it work? If so, then you know for a fact that is your problem.
If you're still getting the data array problem, then it's probably the sheer size of your report and you'll have to create a copy of parametizable reports that cuts down your record set for exporting to Excel.
Catadmin - MCDBA, MCSA
"The only stupid question is the one that *wasn't* asked.