Yeah, I don't think I'll bother sorting that. Not keen on running any export scripts or fiddling more than just getting things running with minimal hassle. I'm doing this on my free time whilst maintaining a full time job that is completely unrelated. Ideally, the publishing process would just ignore it ;-)

Yeah, we could blame Steam for not being intuitive enough regarding the web coding personnel. I guess quota is more important nowadays than skillful intuition.

Actually fixed this the easiest way I could think of; moved the mod source to a "src" sub-directory which I link into the staging folder. Then I can avoid the whole git structure being uploaded via the workshop. Hopefully this works fine - however, if you manually download the mod, then you have to use the files in the "src" directory only (which I'm sure any experienced user downloading mods from Github will figure out... ;-) ).

Of course, as after downloading the Github repo it's always necessary to sync folders instead of blindly extracting.

It seems to be working, so I'll consider this *resolved* :-)
Thanks for your help!