Hi David,
thank you for your answer. I also think we have to either rewrite our integration to CSV or to start using the Excel 2010. I just checked the Event Management Guide and found a paragraph about the limitation Items vs. terms and the maximum number should be about 100 terms per item which is OK for us - our events exceed the 256 terms only because there could be more components of different component types and the Terms sheet contains all of these terms.
Thank you,
Rosta.