Issue: Thousands of errors on import.

Please check my admincp error log. I tried to import my vw3 (vb) to vw4 (xf). Now I have more errors than I can count.

Some of the errors:
Undefined index: alfa
Undefined index: table
Undefined index: threadid
Undefined index: languageid
Undefined index: dateline
Undefined index: adminpermission
Undefined index: prefixid
Undefined offset: 226538 (many variations)
Many errors refer to the import config file vw.php
but also to various other files.