You seem like you will be a great modder here and wish to help you get started.
Step 1) Learn how LUA 5.0.2 works (This is the version of LUA Bully uses.
A) Use the documentation for LUA, this way may be harder but will certainly be better in the long run.
http://www.lua.org/manual/5.0/manual.html B) Or use one of the tutorials by forum members. I suggest mine as it covers LUA and some basic Bully things. c00l's is also a good alternative.
DaBOSS:
http://www.mediafire.com/download/y1f7r6co7lxnemr/Bully+Modding+Tutorial.zip c00l:
http://www.bully-board.com/index.php?topic=18725.0Step 2) Practice, make sure you have all the basics done, and so on.
Step 3) Get involved with the forums and read up on mods to further your modding.
Step 4) Download XFire and add community members. Tell them your a new Bully modder. Here is a list of people to add by username (add more of course but these people will help you a lot and are on often)
DaBOSS54320
tuffjtags (aka Rise To Honor)
c00ld0c26
swegta
madmancorp (half way retired but is still a great guy)
I'm on a good deal and love to help newbies. To answer your question btw use RadarSetVisibility with a boolean parameter of false to disable the map.