Hi, I'm looking for tutorials to create default replacements; from skins, objects to walls and floors.
If you know of any guides or can help me, I would appreciate it

Default replacements of objects are easy. Extract the object from whichever .far file it's in, change it in whatever way you like (just make sure NOT to change the GUID), and put it into the folder that contains the .far file you extracted the object from. You don't need to put the object INTO the .far file, and in fact it's a better idea NOT to. As long as the object is in the folder containing the right .far file, it will override the object that's inside the .far file.

I don't know how to override most skins, since putting a new version of the skin into the folder containing the .far file the skin is from mostly doesn't work. The exception is that I've made default replacements for some of the career outfits by putting them into the GameData\Textures folder; I'm not sure why it doesn't work for other skins.

Walls and floors I've never tried to make default replacements for, so I know nothing about replacing those.

Thanks I'll try again then