Gable - vapor barrier and underlay meet

so dear people,

all transitions from wood to insulation and vapor barrier are done and now a follow-up question

please take a look at the attached picture ...

how do I best make the transition here at the gable wall? at the very back in the corner to the gable there is a rafter,
to which I would attach the vapor barrier with adhesive and tape.

the underlay membrane, which I want to install on the gable wall over the gable stones in front of the insulation
(do I have to do that necessarily???) I would also end on the rafter.

is that okay like that???

thanks and have a good weekend. ob

One more thing: can I coat the beams with something or protect them against moisture, which are visible in the [gable masonry]?

Thanks!