If you're going to make a request like this, at least link to the mod in question.

A link to said youtube video with more information would definitely help.

Well a reverse image search yields no results, where did you find this? That looks more to be a 3D Render than a usable game model.

@ShikangYan clearly didn't read it very well. From the bottom of the OP:

/edit ReN 12.11.2020 : this thread is actively monitored and requests for mod approval will be purged after being followed up upon

Link your mod on that thread and one of the admins will look at it.

If none of them are working then that indicates a problem with your scripthook. Double check that you've installed SHV and all parts of SHVDN correctly, as well as the pre-requisites that come with OpenIV when you install that.

If you're building a map that big, menyoo is not what you should be using. Its outside of my remit, but you need to be looking at creating a Ymap in codewalker. Menyoo for props is horrendously inefficient for memory, which is why the limit is there.

openiv has a powerful search function. Search for handling.meta and pick the one in the dlcpack that the Oppressor was released with. If you don't know which that is, search for the oppressors .yft file, then search the handling meta

not without more detail, no. Have you checked the openiv.log file to check that the relevant dlcpacks are being loaded? Have you confirmed that the mods are installed in the right place? do you have the required pre-requisites if there are any?

Its still spawning the buffalo's tuning parts, and not your Mustang mod. Make sure you've installed the parts to the correct directory, make sure there isn't a patchday folder that is replacing them

Well the source code for menyoo is freely available from Github, if you want to look at it yourself. I run both SNT and Menyoo in parallel and have done since I bought the game, I've never had an issue between them.