Just want to input what fixed my ctd in the Bannered Mare problem. I had finished with the Greybeards but not gone back to Ivarstead to finish Klimmek's quest. It was at this point that Bannered Mare problems started for me. Once I went back to Ivarstead and finished Klimmek I could enter the Bannered Mare again. Then continue the "In time of Need" and " A Night to remember" quests. Don't know why it solved my ctd issues, just passing on what worked for me.