You want to use your PC as HTTP sever? Good luck with that .
Anyway, you simply need a HTTP server (eg. apache) and provide all the files that are in mods/deathmatch/resource-cache/http-client-files. The best way usually is to have an extrenal HTTP server on the same server as the MTA server and just create symlink to http-client-files. But when it's on a different machine then that's a different story.
When I create a browser in-game it always requests some .dummy file from my web server, and i just ask why? I don't request it anywhere, it does it by itself, which it really shouldn't.
The stereo upgrade should enhance the radio somehow, i never noticed any difference though.
Regarding headlights, i think that those are extra lights that can be put on some vehicles (although they don't emit light). I remember that from singleplayer, but i can't find them here so I can't tell you their IDs.
What? I guess the issue is that those files are defined in meta.xml but are missing, that results into resource load failure.
Either provide those missing files or remove them from meta.xml, but if you remove them you may encounter errors/warnings if those files are needed by client scripts (depends on how they are written).
Yes but you have to add it to meta otherwise it wouldnt be avaible on the http server, put download="false" to the file in meta and it wont be downloaded by players at resource's start.
I doubt he meqnt this, id say he wants to change the sign in HUD, either make your own HUD or maybe if its a texture then change it using shaders, but im not sure if it is a texture.
The expprted function is not dependent on anything else in the resource as far as i can see so just copy it to the resource in which you're calling it. It might even be a bit better for performance than calling exported function each frame but i cant confirm that, its just what i think.
All client files are avaiable on internal http server ao that players can download them, for example http://127.0.0.1:22004/login_panel/song.mp3 or something like that, of course you have to change the IP and Port to server's values since client doesn't know them (well, it does but its not accessible through scripting).
I myself am sending data from xml to client in form of a table.. what i do is request the data using triggerServerEvent and then on the server send it to the client using triggerClientEvent, the element data would work as well.