I'd rather reply here, as other people may want to know this ...
The mapper consists of two parts - a mapper module (mapper.lua) which is pretty generic, and does the actual drawing of map.
However for it to work it needs to know information about a room (eg. what exits it has), and its room number.
This is where the complexity arises. Various front-end plugins have been written for some MUDs, particularly the IRE MUDs and Aardwolf, which use the ATCP (or GMCP) protocol which fairly easily passes this information down.
There have been a couple of other front end plugins developed which try to deduce a "room number" by hashing up the current room description.
So unless someone has written a plugin for Elendor, them I'm afraid not. It's not particularly hard, and there are some examples on this forum of the general idea. However since there are around 1000 MUDs, and it takes a day or two to get the plugin to work, I don't personally have 2000 days free to adapt it to every possible MUD. But if you know someone with some scripting experience, they should be able to look at one of the existing ones and modify that. For example this one for Materia Magica:
http://www.gammon.com.au/forum/?id=10667