We're using UR18 (build 4374) on client/server and still having problems with Chrome with CRM 2011.  Are you sure that UR18 fixes this problem?  We have ribbons that don't show active, we can't export to Excel, and sometimes changes made in a window don't take - all problems i think are described as being due to the deprecation of showmodaldialog.  So what is the solution since UR18 doesn't seem to fix it?