Your error or problem is clear.
When my game was in R15 It worked perfectly i switched to R6 and when i hold somebody with my cuffs i cant move. When my co-owner grabs me he can walk with me smoothly.
The moment when i sit was when i tried to fly with fly2
Yeh, these are most likely not going to work with sitting and flying.
It may be that the admin you use messes with something, but the cuffs aren’t broken, they’re just not working with system you seem to be using here, but at the end of the day I don’t see much point of sitting/flying with somebody with cuffs.