Hi Chris,
This worked very well for me, I already had some git hub pages so just added another directory https://git.johnj.info/tiddly/
Took a few goes to get the settings to stick but I got there. I also found if I had two browsers open saving failed. Get the odd save error, but it seems to sort itself out in the end.
Not sure what I am going to do with this as I’ve a couple of other Tiddlywikis, but it is fun to play with.