You do not need to add next-hops for subnets that are directly connected to the router--they are automatically inserted into the routing table as direct routes.
route 10.0.0.240/32 next-hop 10.0.0.26; <<----- I added this per your instructions route 10.0.0.0/24 next-hop 10.0.0.26; <<----- Do I actually need this? I added it myself.
Do not forget to add the L3 mapping to vlan 400.
set vlans vlan-400 l3-interface vlan.400
If you can add a topology diagram it could help answer the other questions.