eSignature (electronic signature) extension for espocrm

[shootify]

I am trying to install this extension, i previously had installed the original esignature V 4.0.3 from telecastg i have espocrm v9.2.7 so i trying to follow the instructions shown here for my specific version, however when i try to install the application i get this error, "Error 500
It's not an Installation package." whats wrong?