Hi Eva,
What is the exact version and patch of BO being used. Are you sure its just a table addition and you got a "Universe with same name already exists, do you want to overwrite" warning when you exported.
If not, then probably the internal CUID has changed and hence the problem.
In that case, you can get the original copy from a previously backed-up location and then try this again.
Thanks,
Prathamesh