TS2K Strategy Performance Report Error

["ndtrader" <ndtrader@xxxxxxxxxxx>]

I am getting an error message:
Error creating new report {20007]
Invalid cell reference
Status 95 (or 100)

My first guess was that my system was too profitable and made TS2K choke :-)
But it turns out the message only appears for long charts (over 100k bars).
KB has no info on it.
Anybody else encountered this, and what can you do, except using fewer bars?

Thanks