I'm having this exact issue on my locally installed version of Kiln. The kicker is, I have successfully set up dozens of repos and branched them. At first, a few branches would randomly fail when I tried to create them, but I could go to a different repo and branch. Now, however, I cannot seem to branch any of my repos.
I've tried different browsers, etc. On my activity screen, I see the following:
repo-name » repo-branch (Deleted) created as a new branch
As if it's getting created then deleted. The linked post mentions a routing issue; could this issue still exist? I'm running the latest Kiln (I believe, just bought and installed late last week).