Wow azuriolinist!
I tried this back in late-2018, when it was just the prompt bit.
Come back to Arm after 2 years, and am amazed at how much it has progressed.
As with previous poster, I had problems with line-breaks between room tiles and exits.
I followed the suggested settings (colors + brief prompts), but could not get Arm to stop sending the newline.
This made the mapper impossible to use.
I ended up just configuring a new multi-line trigger named,
newroom (2-line).
The below regex shouldn't ever overlap with the existing
newroom I believe (due to ^ and $)
Line 1 (perl regex):
^.*(?<!])$
Line 2 (perl regex):
^\ \[((?:(?:, )?(?:N|E|S|W|U|D|Leave))*)(?:(?:, |Quit|Save))*\]$
AND / Multi-line (delta):
1
Script:
raiseEvent('onNewRoom')
room = multimatches[1][1]
local longDirs = {N = 'north', S = 'south', E = 'east', W = 'west', U = 'up', D = 'down'}
local exits = multimatches[2][2]
exits = string.gsub(exits, "%a", longDirs)
map.prompt.room = room
map.prompt.exits = exits
raiseEvent('onPrompt')
How it looks like in Mudlet (imgur):

Thought I'd share -- in case someone finds this useful.