How can I get internet from VLANs on Tomato as secondary router?

Hi - I've been searching and trying various options with no luck. I'm starting to relaise that a little knowledge is a dangerous thing, but I love learning and solving problems, so if anyone has the inclination to help I'll be extremenly grateful!

I have two routers: a BT Home Hub 4 (very basic, ISP provided) and a Linksys EA6900 with Tomato 1.28 by Shibby. I also have a Netgear Smart Switch.

I initially replaced the BT router for the Tomato one to get all the benefits of VLANs, parental...

How can I get internet from VLANs on Tomato as secondary router?