I added the 5 character CustomerID for each customer. It gave me a rule
validation error. I removed the 5 character requirement from the table and
the customers form and it still gives me the validation error. I haven't
been able to find out what rule is being violated.
The only other thing I can see is that CompanyName is a required field,
so you'll get an error if you try to import any customers who don't have
companies.