Regardless of using the OOS plugin, I've been getting stuck along the first wall in City of Sarn, the bot will run up and down along the wall for hours.
This isn't new in the 1.3.1 model, it was happening before.
Please see the "Known Issues" section in the BasicGrindBot Guide. You might also want to checkout the info in the other guides there as well. In short, what WhereIsMyMind mentioned, it's a currently unfixable issue.