When I try to run mame scan to get the .rom .map files, nothing generates in the files?
Had this problem for a LONG time (was tearing my heair out).  two things come to mind:
1) Make sure that the roms (.zip format) are in the directory that you say they are in.  Doesnt hurt to double and triple-check this.  I simple stupid typo and the whole thing is kaput.  Also, make sure of the CaSe of the directories.  Upper or lowercase DOES make a difference to mamescan.
2) My problem was:  My .zip files were all uppercase, and mamescan doesnt like that.  I changed them all to lowercase, and now it works like a dream.  Found a little shareware proggy called "ChangeCase" or something and it made this quite simple.
Let me know if this helps ya,
FJ