There is a very important topic I want to address,
For anyone using glide64 to load the textures, the reason it's crashing or not uploading most to all of the textures is because Project64 can't load that many textures. Basically it's a memory problem. There is a resolution
Install Large Address Aware and patch it to your PJ64 which will give your emulator the ability to run more memory. I will warn you if you are using a potato computer as Large Address Aware requires at least 3 GB of Ram. I'm guessing if you don't have 3GB of Ram it's rip. Also note that when running No Mercy, you can no longer accsess the graphics option as that causes the emulator to crash.
So far I used this Mod as an example because this mod uses A LOT of textures and with large address aware patched in my emulator I can now have the enjoyment of playing with none of the texures missing.
tl:dr If you're crashing or a good amount of textures are missing, it's probably because of memory issues