When I download a car’s .lua files (made in 1357), and put the files into their respective folders, the game does not see them. I go to the sandbox, and none of the files are there. In the files, the version shown is 1353, but this is also the case in the files of the cars that I have made (and work). What should I do?
Edit: The engine is there, but the platform and model do not appear.
Did you put in both the model and the platform file (in the right folders of course)?
Yes, I am certain they are in the right folder. To be safe, I tried switching them, and it didn’t work either.
Could you please upload the files so that I can check or is it secret stuff? 
I’ll PM them to you.
All fine for me, the platform appears in the platform manager and I can load the model.
Should I run the cleaner?
Edit: Ran it, and it worked fine.