This:
/interface bridge port
add bridge=LAN-bridge interface=sfp1 internal-path-cost=10 path-cost=10 pvid=5
interferes with:
/interface bridge vlan
add bridge=LAN-bridge tagged=ether8-trunk-SW1,sfp1 vlan-ids=5
If it is a trunk, you should not set it’s pvid on the port. Unless it is a hybrid port.
Have a good look at this great topic:
http://forum.mikrotik.com/t/using-routeros-to-vlan-your-network/126489/1