Development on NVSE has been continued by hlp. The memory patch from sheson has been ported to work for FNV in NVSE v4.2beta3 on the NVSE site.
To get it to work you have to go into data/NVSE and create an ini with the name "nvse_config.ini".
Then open the ini and add this:
[Memory]DefaultHeapInitialAllocMB=400 <-recommended value
The default value is 200 and the hardcoded max value is <500. I've used 400 and I haven't had any crashes in conjunction with the 4GB loader and ENBoost. I've tested it for about 10 hours with the mods I have on the guide I made for FNV, plus some weather and lighting stuff I'm testing right now, with no crashes, ILS, or freezes.
Without the patch I was getting a lot of slow down with the inventories and pip boy taking almost 2 seconds to load after a couple hours of playing, but that is completely gone now. I played for about 4 hours straight last night and didn't get any problems.