Selecting "Latest" as the revision selection when using Source Control (TFS) as the source in Data Compare 12.2.3.4239 results in "null" revision selected. The only work around is to browse the revisions and explicitly select the latest revision.
We are aware with an issue with the latest frequent release of SQL Compare and integration with SQL Source Control. We are aiming to release fix for the issue you have described shortly.
Selecting "Latest" as the revision selection when using Source Control (TFS) as the source in Data Compare 12.2.3.4239 results in "null" revision selected. The only work around is to browse the revisions and explicitly select the latest revision.