I read a model(mesh) creaded by pro*am. I am sure that the model has no error when creating at pro*am. But threr some cracks after I reading the *.vrt and *.cel files? How can I fix the problem? Thank you very much.

You probably forgot to read the couples (*.cpl).

But I cannot find where to get *.cpl file. ???

It's not saved by default with CDSA. You need to use the Couple Tool to do a 'Couple Write...'.

CDSAVE saves couples but as CP commands instead of in a .cpl file. No doubt the .cpl file came after the CDSAVE command so it was never changed - but couples are definitely there.