Appears the only thing holding the big plastic pulley/cleat block on, is the little pin about 3mm dia.

If that pin is compromised, does it fall to bits? Of is it a really tight interference fit (blue tube into plastic) or glued in, or screwed in?

Sure I saw a thread here about replacing that pin or the release button so hoping some breezers have pulled them apart.

Ta

they never break..... :-)

I've bent and snapped a few of the blue RDM ones. You can remove the button but you can't remove the black piece with the pin. I'm guessing it's glued on as I've never compromised that or even had it come loose. I think the pin just adds extra protection. Though it could be just press fit.

Mark won't the tension of the sail hold it in place. If your concerned at all put a rivit in.