I was able to get the tunnel up . Had to create a certificate in the Checkpoint PKI export it and import it into Fortinet device. Also had to run the below solution to change what the CP presents when as the peer id when it connections.
https://supportcenter.checkpoint.com/supportcenter/portal?eventSubmit_doGoviewsolutiondetails=&solut...
(PS I didn't have to reboot as it says, just had to run the below)
Command will be “source $CPDIR/tmp/.CPprofile.sh”
I had to import the Checkpoint CA Cert into the Fortinet and add the Subject as CN = MyFirewallCertificate Name
Anyway, not P1 and P2 is up but I'm having a routing issue. I have a route that points the 192.168.0.0/16 network inside but the external VPN network is 192.168.51.0/24 . Since this is a more specific route it should take precedence but traffic is ping-ponging. Hitting the firewall and then being sent back in. I didn't create a specific static route as I assumed the connected VPN would create a dynamic one.
Any pointers on how to troubleshoot ?