I've been having a trouble recently.
When I try to SaveAs an item, it doesn't create a ItemRevisionMasterForm.
Then I tried cleaning all my preferences and it worked for 2-3 days, but today it stopped working again.
I tried changing the preference "TC_Enable_LegacySaveAs" and it worked on teamcenter.
But my problem is I want to save as on CAD softwares. SolidEdge and NX.
When I click to "SaveAs" on CAD, they seem to don't use the "legacy save as preference", and they ignore the ItemRevisionMasterForm, creating just and Item and it's revision..
You can find some images attached.