Okay after downloading my own map file I discovered that when I uploaded it the sever it added that long string of numbers to the front of it. I hate split archives...
Anyways to anyone else who gets an error when trying to extract the Rar file just rename 616799-Latus.part2 to 61679
8-Latus.part2
Unfortunately re-uploading the file wont help in this case.
To those who can't open Rar files you can get a free trail version of the Rar extractor here
http://www.rarlab.com/
I have worked with 7-Zip files before, but I could not compress the archive below 30 megs (which is the max a single post could take) so I decided to go with Rar format instead.