canon mirrorless shooter (not using nauticam): dome(s), BBAF position, etc.

I need a bit of help from canon shooters to converge on housings (except Nauticam, that i know), until i find a way to test them in real life, at least on land.

I have an R5ii, but it guess it applies to most Rxx.

1) How are the position and friendliness of the 2 (or 3) AF buttons (AF-on, * , and [-]) on Marelux, Isotta, Ikelite and Sea&Sea (if someone has one yet?)

2) Anyone found a solution to use a single dome for canon 8-15 and a rectilinear (like the RF 14-35) which is not the 230mm ? How bad would the 8-15 look with a 170 or 180 dome (compared tot 140 assuming the curvature of this one is the best?) ?

3) Anyone using the 8-15 with the canon RF 1.4x teleconverter instead of the Kenko (with the hack on the commlit EF-RF converter) ?

4) How complicated it would be to 3D print a zoom gear for the canon RF 24-50 lens for non Nauticam housing ? (to eventually use the WLL1)