No, VSX provisioning tool does all of that onto the VS directly (as if you were doing it in SmartConsole).
For creating a VTI, disable anti-spoofing on the new VTI interfaces, but for any other interior interfaces where you have downstream BGP peerings, set those interfaces to "Defined by routes".
When creating a VPN community, you will want to use route-based VPN anyway, so use VPN domains per-community on both VPN peers for the Star VPN, and use empty groups (to trigger the VTI).
Of course, your VPN Encryption should be using IKEv2, and Tunnel Management "one subnet per gateway pair" [IKEv2 Universal Tunnels).
In Gaia CLISH, on EACH VSX gateway where the VS is hosted, you'll need to configure the same router ID for all instances of this VS on all gateways, and copy/paste the BGP configuration in CLISH again on EACH gateway hosting this VS and in VS-context:
ssh vsx-gw1
clish
set virtual-system 5
set router-id 192.0.2.255
set as 65530
set bgp external remote-as 1234 on
set bgp external remote-as 1234 peer 192.0.2.1 on
save config
Repeat that exactly, on vsx-gw2, and vsx-gw3, etc.
Install policy, wait for VPN to come up. Then SSH to the VSX gateway where the VS is ACTIVE, run:
clish
set virtual-system 5 #or whatever
show bgp peers
Only the ACTIVE VS (on whichever gateway) will show the BGP peering; all others will show Idle. Don't be fooled, and don't troubleshoot the wrong thing.
Hope this helps!