As a newbie to modding, I have been following the guide in https://wiki.beamng.com/Introduction_to_Vehicle_Creation and I can't find out how to enable the exporter Plugin, can someone please help me and explain to me how.
Once you've installed the add-on just check the box and make sure to save user preferences. This walks you through it pretty well: https://wiki.beamng.com/Blender_Exporter_plugin#Setup
I'm using the 2.79b patch from May 23 I believe. I have not tried this with 2.8 They have a new version from today I have yet to try, but it should still work. https://builder.blender.org/download/