Look in your Event Viewer and get the ModuleId for the problem form.
If you have access to your SQL Server Management Console run the Script below. It will work from Host > SQL but the result is hidden in the page Source If you can get the entire content send it to steve at this domain
I also have the next version ready if you want to upgrade. This will not fix the existing problem but will get you access to the Export Import menu. This version does prevent this problem from happening again. If you decide to go with the new version you will still need to export and send to me for repair
Select FormDefinition From C5SLLC_Form Where ModuleId = ###