For just that one vehicle you're better off leaving the global well alone and changing the name in the vehicles.meta. You are able to type freetext in there. For example, you can change LAMPADA to Alfa Romeo

if you want anyone to do anything about this, it would be a good idea to mention the account and mod you're referring to.

I had some comments and criticisms to provide the author of the Elegy RH6 however it looks like Reyser has stepped in to close the comments. Please can we have them re-opened to allow those with feedback to properly advise what can be done to improve.

physics, graphics and ai are all unique parts of the game and separately controlled. You're unlikely to find a mod that does it all. Most graphics mods utilise OpenIVs package installer, so that makes things a lot easier. Physics and AI are more integrated and hard-coded, so you can't really modify that. There are script mods that fine tune the AI within the limits of the game, and they are as simple as dropping the file into your scripts folder.

@MARK2580 Thats simply not true. Cop cars ambiently spawn all over the map at certain times of day. You can check for yourself in the VEH_COPCAR popgroup within the base games popcycle file.

you can simply create your own popgroups for the firetrucks and ambulances, just add their entries to the popcycle file. My popgroups generator has a popcycle edit tool that can do that for you. There are no special requirements for a given vehicle to drive in a given popgroup though, you can add them to any or all of the popgroups and they will spawn ambiently. They will not respond to emergencies though as those vehicles are spawned in as part of scenarios

Speak to the moderators of that website? That url goes nowhere though, I'm not sure how you expect anyone here to help you.

Unless of course you mean this site, gta5-mods.com? In which case just click report on the mod page

fDownForceModifier

Because 5Mods is a primarily single player mod site. MP only mods are not permitted, and should always have an SP equivalent. That and the site is barely chugging along as is, we are unlikely to see any changes to how the site works as the way it is written makes it very easy to break the site if anything is changed.