OK, I made a detailed post on how to setup and use OBS recording software for those who are interested: https://community.freeriderhd.com/threads/how-to-screen-record.12718/#post-273813 BoostButt I think the reason it is greyed out might be because you didn't open FRHD in a window first. If it still doesn't show anything, go ahead and dm me on discord and I can help sort things out for you. Also take a look at my new thread in case it helps.
https://www.freeriderhd.com/t/544020-vivre/r/anonyymi ghosted this for the past couple days for fun not realizing unknown-rider's ghost had a feat anyways,