possible multiple geometry collision bugs

[ghost]

I was doing a map to torture and fix bots, using as tight as possible geometry. When walking the map myself, I noticed various behaviors which seems buggy. Overall, when walking down a slope, one can "tolerate" a ceiling which is lower than if trying to walk the same slope up (in the other direction). This is especially true when crouching.

Joining the (pretty bad) file I used to notice that:

map-unnamed_src.zip

As a reminder, here is the description of naked humans bbox:

name              "Base Human"
model             human_naked
modelScale        1.0 
skin              default
shadowScale       1.0 
hud               human_hud

mins              -15 -15 -24 
maxs              15 15 32
crouchMaxs        15 15 16
deadMins          -15 -15 -4
deadMaxs          15 15 4
zOffset           -2.0

viewheight        24  
crouchViewheight  7
shoulderOffsets   -10 15 0