hello the singatures of drivers u can set in the settings in : My coputer - right click - properities - Hardware - Signatures

.7z is the file wich could be extracted with WinRar or any other 7z extractor (look for google) it is like zip.

The blue screen you get it ussualy after you install the FULL firmware and you can recognise your palyer as a DRIVE, but anyways it is not necessery, so dont be much stressed about it.

What next? Follow the dead player recovery guide -> find and insta 1. full firmware 2. dump !

Uttilities ? USe the ones i sent you -> Product tool 4.19 or check the download section for the classic ones.

hope i help... gl