This is maybe not the best thread to get pyps3checker support. I think it might have been better to post in one of @littlebalup pyps3tools threads.
Do you have Python 2.7 (specifically 2.7, not another version) installed?
If you do, you can use the repo files directly.
If you don't, you should either install it or alternatively extract the files inside the "standalone zip archive" at the root of the repo.
The batch file for drag & drop expects python to be installed at:
c:\Python27\python.exe.
If the path is different in your local installation you need to edit the .bat file accordingly.
Imho you should just use the command line, open the command line console, use the cd command to set the appropriate folder & launch:
checker.py dump.hex