To Summaries
A)
Name/DisplayName "Python 3.X (64-bit)" or "Python 3.X.Y" (64-bit) "Python 3.X (64-bit)" would match the install directory which is \Python3X (this should be \Python3.X)

Display Version should start with 3.X.Y or 3.X.Y.<build number>

version DWORD in the registry does not need to be set but if set would need to be 3.X.Y
B) Registry being placed in in the wrong location
HKU\<User-SID>\Software\Microsoft\Windows\CurrentVersion\Uninstall\{GUID}
should be going into
HKLM\Software\Microsoft\Windows\CurrentVersion\Uninstall

C) Suggest the default install dir is
"c:\Program Files\Python3.6" instead of "c:\Program Files\Python36"