Hi Paul;
I am using IIs on W2008R2 and IIs is version 7.5 on that MS-Windows system.
FYI: For PB Web Services, is use PB's MSI packaging and these install great. I loaded the PBVM for these using PB'S "Packager" application to create the PBVM install.
As for the last part of your question .. I Assume that you are using the old Webforms feature to which I cannot comment any further as I am using Appeon 2013R2. I am not sure if Webforms will even run on IIs 7.x
Good luck!
Regards ... Chris