This looks like the log from the second time it failed. Though I'm kind of surprised by the fact that you were able to run the editor twice, usually the replay wouldn't be visible in the Replay Viewer after the first failure (because the mod moves it into the "raw" folder). Did you maybe create another replay with the same name after the first one failed?
I've fixed multiple issues with the Replay Editor by now, so chances are the one you had was fixed as well. Unless you're able to reproduce it with the latest version, I doubt it's worth pursuing.