Signature to be used when sign the document

[GlamBytesGeek]

Hello,

Thank you for the project.

I'm interested in understanding what the base64-encoded external signature refers to. I attempted encoding my private key, but it didn't successfully apply to the placeholder. I also tried converting my private key to cert.p7b then apply to the placeholder also without success.

I suspect it must be related to the document digest, but I am lost about what is the relationship in between cert.p7b and document digest.

Could you please advice?