Hi Jerry,
I've successfully installed the AutoIT library on Windows 10 for python 2.7 and python 3.5 (32 and 64 bit). I've also written a test case that works with the windows 10 calculator but I haven't found the time to make it ready for a release.
I think the problem you're facing here is that you're trying to register a dll and you haven't run the installer as administrator.
If you're still getting the same error when running as admin, try running the command "%SYSTEMROOT%\system32\regsvr32.exe /S C:\Python27\Lib\site-packages\AutoItLibrary\lib\AutoItX3.dll" manually from an admin cmd prompt.
If you want to get the 64bit version working, you need to get yourself a copy of the autoIT library from their website and extract the 64bit dll and register it instead/as well.
I've attached the windows10 test case.
I'm happy to share my modifications if you or anyone else is interested in releasing a new version that covers python 3 and 64bit options.
Tom