TGIT should allow cloning and/or creating from within a non-empty repository
TGIT has no GUI interface for cloning a repository or creating a repository from with a non-empty folder of a git repository. It should have, since this operation is perfectly legal using git itself. TGIT does allow cloning or creating a repository from within an empty folder of a git repository through the Shift-ContextMenu interface. But there is absolutely no reason to distinguish between an empty or a non-empty repository in this case since cloning or creating a repository within an already existing repository folder does not affect any of the repository files already in that folder.