When upgrading my computer from XP to Windows 7, I wanted to keep the ancient Photoshop 5, as I had a license and I was used to it.
Unfortunately, the installation did not work. After some Googling it turned out the the 32 bits Photoshop used a 16 bit installer that was incompatible with a modern operation system.
Just copying the files does not work, as Photoshop uses dozens of registry entries and I was not willing to type them in manually.
I downloaded a shareware file monitor and a registry monitor. The 30 day limit was no problem, as it is a one off excercise.
I installed Photoshop on a clean XP machine with the monitors on.
As a result I had a registry diff and a file list.
The 64 bits Windows stores the 32 bit DLLs and registry setting under Wow6432Node and SysWOW64 (in stead of system32), so I hat to do some "find and replace" on the registy file, which is here (with a text extension to stop overenthusiastic web security blocking it).