I downloaded and installed some mods which i read somewhere go well together, some of them are:

-Rens Beauty pack
-Nec mystic high elf
-New frostmourne sword
-Female eye candy (nude)

All of them are working expect the Female eye candy (nude) one.
It is not appearing in Olivion mod manager aswell, any idea what ive done wrong ?
It says its the OMOD version, what is that, another main file that i need to get it to work ?

Female eye candy won't appear as a .esp because it is a mesh and texture replacer. Download OBMM if you want to install the mod using the .omod file. Or you could just copy the meshes and textures folders into your oblivion/data folder.
i.e oblivion/data/meshes/characters/_male/(then the .nif files)
It shouldn't overwrite anything important but make a back up anyway.

I hope this helps

EDIT: Sorry did you say you had oblivon mod manager (OBMM)? Just open the .omod file with this application. Full instrutions are on the link above.

oblivion mod manager = obmm... ?
that solved it, got it working ! thanks m8 ^.^

one more thing i want to ask, these mods that im using atm, will they still work if i install shivering isles ? wont they crash the game and force me to reinstall it with all mods ?

also will be installing Oblivion: make it look pretty mod, thats bound to cause problems if i get any expansions later on.

no
shivering isles is merly an extension of oblivion
it ha sno effect on the mods ( with the possible exception of mods like ooo which overhaul oblivion )
im running around as a tabaxi on shivering isles with various mods installed