When installing the 4.0 beta, I was unable to have it install to IIS as a new web site. It said it detected that IIS was not running or installed and wanted to do some manual configs for me. As I have 4 other websites running on IIS right now I definitely didn't want that to happen. I tried multiple ports to see if that helped but it didn't.
Using Windows 2008 (non R2) and IIS 7. This is also a Domain Controller. Most likely, once this goes release, I'll be running it on a VM member server with 2k3 R2 installed on it tweaked solely to run LS.
I was able to successfully install the program using it's own web service. For now, I've just set a redirect in IIS where the old 3.5 LS used to run from but I really want AD authentication for accessing the inventory web site.