[Muas]

Kind of OT, but I noticed the markings on the Mk.Ib... how exactly do you specify which roundels to use? It's probably a stupid question with an obvious answer, but I've been wanting to apply the early-war roundels to the Spit I and Vs for a while now.

Roundels and overall country markings are coded for specific aircraft acording to year and theatre of operations - its not meant to be customized by the player - they can only be modified by a specific mod.
In this Sea Hurris mod, specific country markings, designed to work along with the default skins, were custom made and included in the package for added realism when using the default Royal Navy (RN) scheme as its supposed to be.

I also noticed the bug of the instrument panel (...)

It's on the list. I'll address this issue as soon as I can.