How to make an RF2 skinpack

Simple flow overview

1. Collect all the skins for the pack, as mas files
2. Separate them based on car.
3. For each car you'll be making an rfcmp of all the skins for it. You can share these individually if you want.
4. Once you have the rfcmp for each car, you make a multi-mod rfcmp for all the cars. This makes one big skinpack that you share.

Making an skin rfcmp for a car

1. Open MAS editor
2. Create a folder on your desktop or wherever for this car.
3. Create an empty file in this folder called <carname>_<version number><seriestag>.rfcmp - to get the correct version number, go to the installed folder for that car in your game install and find the highest EVEN numbered version and use that. For example for the Aston Martin GT3 I'd name that file astonmartingt3_v1.76ovg.rfcmp (the highest even version number at time of writing).
4. Make sure you have a blank mas editor, then click the "Create the package file" button
5. Select Create Single Cmp Package
6. In the new window, next to where it says <Add New Component> click the "New" button.
7. In the box that appears type the name of the car EXACTLY as it is show in the Installed folder (so for the Aston you'd type AstonMartin_Vantage_GT3_2019 here). Press OK
8. Next to the "File" drop down menu there's a cabinet button, click it. Find the empty file you created above and select but DO NOT OPEN it! First you need to increase the version number by one, so in the example I gave above in the text box at the bottom of the open dialog I'd change it to astonmartingt3_v1.77ovg.rfcmp. Then click open (it does not matter that this file doesn't exist).
9. Below the drop down box, tick the Update From: tick box and enter the the last even numbered car version (in my case 1.76).
10. In the version box to the left enter the ODD version with series tag (again for me that's 1.77ovg).
11. Select Vehicle in the type drop down box.
12. Click the cabinet button next to the MAS Files window. Select all the MAS files that you have been sent
13. Click package and install. The package file with the name <carname>_<versionnumber><seriestag>.rfcmp will be located in your rf2 packages folder by default.

Congrats you've made the package for this car, repeat for all the others. You can just upload these individual files and have people install them or continue on to the next step to make one big package of all skins. You can also reopen these files to add additional skins as needed, but be aware people will have to uninstall and reinstall them for that to work. You can try adding a letter to the end of the version to show new versions of the file to get around that.

Combining Car skins into one Pack

1. In a blank MAS editor, click "Create the package file"
2. Select Create Multiple Cmp Package
3. Give it a name, then click the B button and select a place you want it to save the file to. In the open dialog type in a name for the actual file i.e. OVGT3S7_Skinpack_v1.rfcmp.
4. Click Next
5. Click Next again.
6. You should be on the vehicle select screen. Scroll down the list selecting any car that has the series tag in it's version (that you made when you were compiling the skins in the previous stage). If you don't see the cars you made previously here, you need to have them installed in your game. You can uninstall them later and then just install the skinpack to test that it all worked.
7. Click Next
8. Click Done
9. You should be able to see all the cars listed in the vehicles section
10. Click Package

Congrats you've made the combined skin pack. You can share this for people to install. If anything changes with any of the cars you'll have to remake this again, just make sure not to use the same name.