Hello,
I was able to replicate the issue of the TabName4 field not being populated when using the Product Import and have logged this to our Bug Tracker system to be addressed. I will reply to this thread as soon as an update is available.
If you would like to prioritize this issue to be addressed immediately, please submit a quote request here -
http://www.smith-consulting.com/servi...
It is not required that you sponsor this fix, just if you would immediate attention to the issue you reported.
Please let me know if you have any questions.