I use this script and I've mostly worked with the 1.2 release candidate. I can tell you this thing is slick. The key to making it work perfectly is to be sure your server environment is set up correctly from the start. There are a few utility programs that are required, so make sure those are installed, up to date, and functioning correctly before you install LM.
I haven't installed 1.3 yet, but as soon as I have time I will. I'm already planning on buying four or five more copies - I just need to choose the domains.
Do you guys have an install service? I can't remember and am too lazy to look on the web site