There are standard Teamcenter Rapid Start Item and Item Revision Master Forms available within tcx template.
I see this in BMIDE.
Under Properties I see some runtime properties from that form.
Can I modify these?
I know how to make some of these visible or invisible but don't know how to modify the existing ones names.
The thing I want to do is make some properties of that form go away, and modify some others to avoid creating new form and trying to attach it to item or item revisions.
Making the form properties visible, invisible etc should be doable from Property constants tab in BMIDE.
You could change the display name as well from 'Localization' tab in BMIDE (located along property constants tab).
The OOTB form properties may not be editable. Your requirement can still be addressed by displaying selective attributes on Item Revision (through stylesheets or compound properties onto rev, though I prefer stylesheets) and hide the master forms (item / item rev master forms).