Bridging internal switches on RB2011UiAS not working

RouterOS Beginner Basics
1

I am getting a little frustrated on what should be a simple setup (note - I use Graphical WinBox setup ONLY because I am simple!).
I Just cannot get internal routing between the two switch groups (ETH01-05 on switch_1; ETH06-10 on switch_2) ETH01 cannot talk to ETH06 etc.
I know that there are two physical (Atheros) switches in this unit and I SHOULD be able to Bridge between them.
Currently I am resorting to a physical cable between ETH05 and ETH06. I would like to remove the cable! (and gain a gigabit port back)

I have:
my RB2011 ETH01 connected to my home router and using the home router DHCP.
an IP address assigned to ETH02 as static so I can access it from my connected PC.
ETH01 to ETH05 in a port list called LAN_GB
ETH06 to ETH10 in a port list called LAN_MB
list LAN_GB attached to bridge_GB
list LAN_MB attached to bridge_MB

It should be as simple as - remove patch cable, attach list LAN_MB to bridge_GB - This Does Not Work.

Pulling my hair out here.
Any Ideas?

2

Go to Bridge, click the plus sign and create a Bridge…
If a Bridge already exists do not create a new one…
Go to tab Ports, click the plus sign and select all the ports you want to add inside your Bridge…
Your ether1 is connected to your router, so if you add ports 2 to 10 inside the Bridge, they will all be able to communicate with each other…