For those who get the error "Interior map hasn't loaded, return to the vehicle now" with the RV interior mod, follow these 5 steps:

1. You need to start a new game (save) with all mods you have now + with new maps you wish to have - lets call it MAPSAVE
2. Once it loads, exit game, you are done here
3. Go to your save folder (i think for most is C:/USER/Zomboid/Saves/)
(your save is within one of the folder, i always play Sandbox so it is Sandbox for me)
4. BACKUP YOUR SAVE FOLDER - kinda usefull you know.
--------- Now the fun part ----------
5. Copy and overwrite file "map_ver.bin" from that MAPSAVE folder to your save

IF you didn't visit that part of map you are adding YOU ARE DONE, GOOD, FINISHED -> GO PLAY