Our product is just used to edit the content of an HTML field. All versioning and workflow tasks are performed by the MOSS 2007 code. This means that if you can revert to a previous version with the original rich text editor, then you will be able to do so with our editor as well. I can confirm that you can revert to previous versions for the WCM field and lists that support it (e.g. Wikis). But as I said, the versioning support really depends on MOSS and not our editor.
the Telerik team