limit on the number of 'field-set' lines you can send to the ITS?

We've just upgraded the ITS to version 6.2. I'm trying to send a lot of data using the field-set macro. This worked fine in the old ITS. Now when I try and send all the lines the page crashes. When I send just the first few lines the page is displayed ok.

Is there a limit on the number of field-set lines you can send to the ITS? Is this something I can change?

Regards

Karen