To update everyone on this. TMEdit uses certain components of the OS for package generation. This requires at least 1709 to get the correct version of the API, and support for older OSs is not forthcoming. But it is an editor tool so you just need one VM for the editing.
Although the tool works on 1709 and later, the latest released version of Windows will always be the recommended one (well unless they break something in which case I'll say otherwise).