Hifirst from RV042G , are you getting any routes from internet . Firstly check for reachability to internet from router.<<On the RV042G, this port is set to VLAN1, while the port on the SG300 is set as a trunk port. >>from router to switch this port...
using prefix list with 0.0.0.0/0 le 24 , you can call in the route map and you can apply the policy in inbound to neighbor statement of the ISP. using this we can recieve default route from ISP side even though ISP announces individual prefixes