I have a save game (the most recent one other than this one is from a backup DVD I made a few months ago and I would rather not return to it if I dont have to) here:

http://www.cncmods.net/files/saves.zip

If I load it and then press F5 to quick save, it will crash to desktop.

I am running Oblivion with all patches and official DLC.

I am running OBSE 21.4 (the latest version)

I am running the following mods:

Battlehorn Castle COBL 1.0

Skyrim Ingredients for Oblivion 0.7 (including optional COBL ESP)

Fast Exit 2.0

Unofficial Oblivion Patch 3.4.4

Unofficial Official Mods Patch 18

Unofficial Shivering Isles Patch 1.5.2

COBL 1.72

Harvest [Flora] 3.0.1.0

Item Interchange 0.78

Keychain 5.0

Respawning Clams 1.0

Toggleable Quality Prompt 3.2.0.0

Weapon Expansion Pack for Oblivion Nthusiasts 1.03

QZ Easy Menus Update 1.03

Vaculty FINAL

My load order is here:

http://pastebin.com/46SA3vVW

DLCBattlehornCastleChanges.esp is a custom addition to Battlehorn Castle and Battlehorn Castle COBL that I made, its been working fine for months and hasn't changed so I doubt its the cause.

Anything I can do to get my save game going again without having to throw away a bunch of playtime and go back to whats on my backup CD (and also take the risk that playing from there might lead to the same issue again in the future if I have something wrong with my Oblivion install)

Any more info I need to provide in order to help the experts figure out why my game is crashing?

Could one of the Microsoft updates I ran recently (I am running Windows 7 with every update Windows Update offers me installed) have caused this to start happening? The newer NVIDIA drivers I installed recently? Could I have a virus on my machine? (AVG finds none but that doesn't mean my system is clean...)