Normally, I don't advocate fixing these sorts of bugs, but because of Hearthfire's shenanigans Breezehome is now pretty much unsafe to modify in its entirety unless your mod is mastered to Hearthfire (which is currently impossible due to unrecognized sub-records in the ESM). This is a severe incompatibility given the number of mods out there that do edit the house, and it is not known at this point if the conflict can actually be fixed (removing NavMesh Forms in the CK can result in the CK crashing trying to save the mod).
So in essence, the modders are pretty much helpless on this one. If Bethesda does not fix this (which they likely won't), let this serve as a precaution: if you are crashing trying to enter Breezehome, make sure ALL mods that modify that home are disabled.