Thank you for buying the tool, I really appreciate it!
The reason why I haven't allowed a road to connect to itself is that it could have quite a few bieffects that are hard to estimate. I have released a new version that does allow this tho with a few limitations. So you can connect the start and end point together into an intersection now. By moving the points and removing turn marking your players won't ever know that there's an intersection there.
I would still recommend creating two roads and connecting them to create a circuit (the old way) but it's up to you. Often you want some kind of split road or pit stop or something depending on what track you create, so in those cases it'll be multiple roads regardless.
Check out the latest update and let me know if you have any more thoughts! Good luck with your game :D