When upgrading the database I already had on RomCenter 4.0.1, this error came out:
Upgrade v2 database file to v3 Error: Requested value '7z' was not found.
And it doesn't allow me using the existent rom lists.
[screenshot in #225]
Issue #225 was marked as a duplicate of this issue.
Can't reproduce the problem.
Please post the romcenter rdt file.