Passages Use Empty Hexes
You can place passages at hexes you normally can’t build on.
Check the selection panel after placing a passage construction site, if it says "Dome Connection Established" then it’ll work, if it says "Connection Failed!" then remove the site and try elsewhere (white highlighted hexes only).
Press Numpad 6 to toggle showing usable hexes.
Mod Options:
Show usable hexes: Show hexes that can connect domes when placing passages.
Known Issues:
Doesn’t seem to work on xbox?
Ramps will be ignored till you reload the save.
You will get warning messages when trying to place passages in "wrong" places (just ignore them).
I was more concerned with removing limitations than setting new ones, so you can build them in stupid places (if it doesn’t place a complete passage then remove it).
Placing a passage at the life-support/entrance hex works, but you can’t do a manual kink in the line.
Passages overlapping entrances can block drones/colonists from using entrance (use toggle collision button).