I've been away from the game for almost a year. Before the hiatus I could use the "Continuously use BreezySail" function just fine.
Now I just can't check the box anymore. The ship is an Epheria Galleass. It's the same character (Sailing skill at Artisan 2), and the boat is neither damaged nor overloaded.
I've tried what someone else suggested a while ago and switched the display mode from windowed fullscreen to fullscreen, didn't help. No matter what I try, I can't check the box.
I've had this issue a couple times and each time I had to relog to resolve it. It's not happened to me in a long time though. I'm wondering if the game is failing to read the Sailing lvl correctly. Maybe when they merge all character lifeskills it'll resolve this issue.
It was also discussed here: *Solved* Unable to Click Continuously use BreezySail