PC unable to climb the stairs in the Mages Guild in Caldera

I am running Windows 7 64 bit with Open MW 0.35.1. When trying to climb the stairs to the second floor, I get stuck half way up and unable to move at all, neither up nor down. I have attached a screenshot. There is no obvious error, but I have attached my Open MW log file just in case.

(RM-2439 from redmine: created on 2015-03-08 by Rob Wilson, , closed on 2015-03-16 by nobody, duplicates #2442 (closed))