Jordan, answers Inline below
1- Do we need to add the PANW context server in CPPM and/or Palo Alto Networks Panorama Context Server?
[djj] - If you have Panorama then you can just add Panorama assuming firewall is being managed by Panorama.
2- In the Context server configuration in CPPM, do we need to keep the Service Base URL as per the below or we need to substitute the server_ip?
[djj] - Never change it.
3- As there is no authentication (i.e. dot1x), shall we upgrade to CPPM 6.6.x?
[djj] - So you want to leverage onconnect and then use an enforcement profile to send data to PANW, that should be OK.
4- Please Advise if you can provide a sample configuration for our case from Cleparpass and PaloAlto side?
[djj] - Config for what exactly?