Hi Sujit,
I looked at the note and it pertains to PKCS#7 encryption. It does match "import_own_cert: Installation of certificate failed" but the reason's cited deal with a missing roots, unrecognizable data.
I am not getting any error except forimport_own_cert:Installation of certificate failed.
The "sapgenpse import_own_cert" reports finding the PEM-framed base64-encoded ASN.1 Certificate. I have added the root certificates also with the same result.