Actually the config is a bit confusing, some questions!
(1) You have at SIX duplicate set of this rule for specific source addresses. 10.0.0.202, 10.0.0.152, 10.0.0.109, 10.0.0.191, 10.0.0.30, 10.0.0.70 !
add action=mark-connection chain=prerouting connection-mark=no-mark disabled=\
yes dst-address-type=!local in-interface=bridge new-connection-mark=\
WAN1_conn passthrough=yes src-address=10.0.0.70
PLUS the usual expected rule for PCC!!
add action=mark-connection chain=prerouting connection-mark=no-mark \
dst-address-type=!local in-interface=bridge new-connection-mark=WAN1_conn \
passthrough=yes per-connection-classifier=both-addresses-and-ports:2/0
add action=mark-connection chain=prerouting connection-mark=no-mark \
dst-address-type=!local in-interface=bridge new-connection-mark=WAN2_conn \
passthrough=yes per-connection-classifier=both-addresses-and-ports:2/1
What is the purpose of the six rules you have that assign new connection marks to specific IP addressess on the bridge??
I am assuming its so these IPs never get assigned WAN2, but only WAN1?
(2) The difficulty with dischers PCC is that he assumes fixed/static WANIPs, and I was looking for a way around his config for dyanmic IPs........
But I see you are using fixed WANIPs so this example doesnt provide any illumination on the issue.
What I found interesting though, is your use of these rules (dischers first two rules) OR LACK THEREOF,
Nowhere to be found are these ACCEPT RULES.....
ip firewall mangle
add action=accept chain=prerouting disabled=no dst-address=fixedIP-WAN1
add action=accept chain=prerouting disabled=no dst-address=fixedIP-WAN2
Instead you have six rules I have no clue what you are doing......???
...
/ip firewall mangle
add action=passthrough chain=postrouting comment=\
"test_speedtest.net (server 88.149.202.248)" dst-address-list=speedtest \
protocol=tcp routing-mark=to_WAN1
add action=passthrough chain=postrouting dst-address-list=speedtest protocol=\
tcp routing-mark=to_WAN2
add action=add-dst-to-address-list address-list=use-WAN1 \
address-list-timeout=1h chain=postrouting comment=\
"list connection balance" out-interface=ether1-WAN1
add action=add-dst-to-address-list address-list=use-WAN2 \
address-list-timeout=1h chain=postrouting out-interface=ether10-WAN2
add action=mark-connection chain=prerouting dst-address-list=use-WAN1 \
new-connection-mark=WAN1_conn passthrough=yes
add action=mark-connection chain=prerouting dst-address-list=use-WAN2 \
new-connection-mark=WAN2_conn passthrough=yes
....
I don't understand exactly how you can do it and what you get is very complicated.