OK, following looks a lot, but should be straightforward ...
Download lapper, and save to your '/LFS' folder.
Download from
https://www.lfs.net/forum/434-Releases.
I'm still running V7093, but no reason why script won't work with the newer versions.
You can rename this downloaded folder or leave name as is.
Because I use lapper with lots of different layouts, I make a new folder with the name of my new layout, as lapper saves times and drift scores in databases using the track abbreviation. And as I use LA1 a lot, the 2nd layout would overwrite the times/scores of the 1st layout.
In this downloaded folder, in the /bin directory, open 'LFSServers.cfg' file
Change the IP and port numbers on the last line to match your rented LFS IP / port numbers
(e.g. DEF1|gr1|123.456.78.901|59901|./default|default_1.ini|autowork)
In the /bin/default directory, open 'default_1' file.
Change the password to match your multiplayer host password (e.g. $password = "mypass": )
In the same directory, open both the 'admin.txt' and 'superusers.txt' files, and add your LFS username.
Download the 'drag2.txt' file in my post
(https://www.lfs.net/forum/thread/112222-Simple-Drag-Light-System),
and rename to 'drag2.lpr'.
Move this file into the /bin/default/includes folder.
In that folder, open the 'addonused' file, and add the line
include("./drag2.lpr");
All the above files can be opened with your default note app, e.g. Notepad.
To run lapper, click on the 'LFSLapper.exe' file.
If all that works, then when in your server, type "!drag".
If you want to change any of the light colours, you can. For instance "^0•" will show a black light, but if you want it white, you would change the 0 to 7, or 8 if you wanted grey, etc.
Good luck.