OK, Joe ... I've got it going.
Following the link you gave, I was able to download* the (standalone) "bloat" of MS .NET Framework 4.0.
That is:- dotNetFx40_Full_x86_x64.exe ... all 50 Meg of it!
I then installed it OK on a Windows 7 (32-bit) machine. Happily the installation proceeded effortlessly.
FYI: when I tried your Manuals.exe it threw up a message insisting that it could not find the path "C:\SampleManualsFolder". But once I had created that directory (folder) the .exe fired up OK (from, as you mentioned before, any location). I then shifted your sample folders across (into that root directory), and then there they were:- displayed as you had intended. Nice one!
*
By "sniffing" off someone else's Wi-Fi connection ... but let's not go into that now.
