Inklewriter forums on their site? Traffic was slow but the advice was great.
Varytale? This seems like an awesome platform - essentially a milder, more linear form of story nexus with gorgeous user experience that would seem to attract people who also write in twine, and seemed the best chance of attracting book readers to IF.
In April I wrote Ian at Varytale about it and he said that it was on hiatus after “losing a key co-founder.” But if you have an account I think you can still access your work.