Well yeah the keys are theoretically available, for sure, but the reason you can't change that or most other settings at the time is that it's an entire different interface mode. Turns out you're still allowed to use the current tool to paint since the canvas is still visible, but the tools are hidden at the time.
Ideally both the browser and the paint tools could be visible at the same time, like might be allowed in RP 2.0, but they currently occupy the same space so having them both be visible (and therefore accessible) isn't really feasible. RP could be redesigned to require a wider aspect ratio but unfortunately that's no quick job, plus of course it would then not be as usable on smaller screens, and reduce maximum available canvas size :/
The only alternative is to actually duplicate a bunch of commands so they're also allowed in browse mode, which would really bloat the code, likely cause a lot of problems to work through and have to be removed/undone in the long term... Hm, I just spent a while trying to think through possible solutions and really don't see anything ideal for this.
BUT, you're gumix and I know you use REXPaint a lot for great work so... if
all you need is the layer selection functionality (even though you can't even see the selected layer number xD), I've... made a patch for that
. You can download it
here (removed--see newer patch later in thread). I think it works okay, I mean at least it does what it's suppose to in my tests, though hopefully there aren't any side effects!
Note: One feature I definitely use a lot which can help if you're working between two specific images is ctrl-tab, which in the main paint mode switches back and forth between the latest two images as necessary. Very useful! (but I'm guessing you already know about that one)
