I have no experience with UCC (this is about custom designs created by the users, isn’t it?), but regarding the ghost mode I remember it being broken by design, AFAIK it never worked 100% in any official Pangya client. I remember trying it once in Global, I managed to play 4-5 holes until I got stuck, I couldn’t interact with the interface anymore and I had to abort the game. So I wouldn’t worry about it for not working.
I haven’t really worked much with UCC either, I only ever got pointers on how the format works and built a tool for it.
It probably would be easiest setting up a webserver for the endpoints Pangya tries to hit for both UCC and Ghost Mode and trying to make sense of the data and requests and going from there.
Research on other sites mostly went private because a lot of people thought the mainly unstable handling and testing of it was for “production” and private server purposes, I haven’t been lucky on finding a lot of public information on those endpoints either.