Today, for no apparent reason, my otherwise stable NV game started barfing when saving. It was around Primm and on a quicksave. I reloaded, quicksaved again and it crashed. I reloaded ... it crashed before completing. I reloaded, tried saving [slow method] and it crashed. So I played for a bit around Primm, figured I'd try to 'shake it off' or something, and entered the sheriffs house ... and the game saved correctly. After that it would save on entering an area, quicksave etc again no problem.

Until I sit down the game and tried to play again 6 hrs later. No when I transition or save, the game is crashing to desktop. I'm putting this down to my mods, but not for any reason other than I added a couple of weapon mod ... um ... mods ... I'm I'm wondering if they are related, or if the number of mods I'm running is giving me and issue (or the order I'm running then in?)

FalloutNV.esmCALIBR.esm20th Century Weapons.esmLings.esmCompiled Patch.espSorter - Combined.espammoingredientsloot.esp10mmAP-Final.espCONELRAD 640-1240.esp20Ga EMP Slugs.espLFox Bottle That Water.espRangermask.espPlausible Starting Outfit.espRX-Reloading Bench Improved.espRX-Reloading Bench Improved Addon.espMedGrass.esp20th Century v5 ALIVE (Khan).esp20th Century v5 ALIVE (PowderGanger).esp20th Century v5 ALIVE (Vendor).esp20th Century v5 ALIVE (Containers).esp20th Century v5 ALIVE (Other Factions).esp20th Century v5 ALIVE (Fiend).espBetter Binoculars High.espF03weaponpack_v1_0.espModdable Unique Weps.espScopeNightVision.espaaaJNFSniperZooming.espKDS Wearable Backpacks.espWeapon Mods Reworked.espDragonskinTacticalOutfit.espDepth of View Middle.espLeather Trench Coat NV v1.0.espCompanion Sandbox Mode.espLight Step ED-E.espTristans Gun Mods.espdD - Enhanced Blood Main NV.espPipBoyLightx1.5.espNevada Skies.espNewVegasBounties.esprecycSB.espExplosionsKnockDownCritical.espQuest Items - Non-Essential and Categorised.espLucky 38 Suite Respawn Fix.espLucky38MarkerV3.esppopulatedcasino-medium.espBetterLuckySuite.espFellout.espProject13 - Populated Wasteland.espPulse Grenade Recipes.espRiaAmmo.espCentered 3rd Person Camera.espRCSS.espimmersivesneaking.espNimrodDresses.espTotal active plugins: 54Total plugins: 66

You might be able to solve the 'crashing on save' thing, by using FNVEdit and using Master Update Mode.
If you don't have FNVEdit yet, or don't know how to use it yet:
- http://www.fallout3nexus.com/downloads/file.php?id=8629 *Look at the Master Update part*
- http://newvegasnexus.com/downloads/file.php?id=34703

Since you have a lot of mods, I would also advice you to read the section about 'Conflict Detection and Resolution' and 'Creating a Patch Plug-in (Manual Method)'.
I'm having a slight hunch that you might have some conflicts with some of the mod-mods.

If you are using FOMM, then I advice you to first go to 'Help -> Check for update'.
If there is a new version of FOMM out, download and install it.
Check for update again and you will probably be prompted with the message: 'A new version of the load order template is available: Release xxxx. Do you wish to download?'
Click on Yes and then go to 'Load Order -> BOSS Auto Sort'.
To check which mods it doesn't recognize, go to 'Load Order -> Load Order Report...'

I hope this will help you.

If you're getting crash on save, could be a corrupt save ... try going to an earlier save.