Oh man, I ran a CP21 on an AV10 and it was great except for the needing special jets. Theyre real similar to the OKO's since theyre all PWK based
but man, i've run that kit on an e50 and it was a real chore to dial in, felt like it had a really different demand, like tune the topend high RPM and low speed WOT was wonky etc. But that was with a VM which is maybe more forgiving but less tunable, I feel like it'd needed a better balance of main vs pilot, just needle/main didnt cut it. And like usually I'm at a pilot close to half the main, but that kit I think wanted a smaller pilot
the leaky is almost definitely the float needle seat
you have to plug both tubes at the engine side, they've got a lil bung for a vac petcock, and one for oil injector, i just used a small line and connected the 2 with a U
They're pretty sensitive to needle and atomizer, make sure you've got the 2t atomizer (no holes) but I think blocking the air brake just makes the 4t atomizer effectively a 2t. But I think for that kit, the idle jet's gonna be more important and I think it was lower than I'd normally expect.
These are some dusty memories so dont give my thoughts too much weight.