hi,
the 2 internet gateway problem was solved, thanks to "janisk" and mikrotik wiki.
still, i'm wondering, if i enabled the web proxy service, which gateway will be used by the proxy to connect to the internet?

thanks

Web proxy will always use your default gateway to connect to the internet.

Web proxy will always use your default gateway to connect to the internet.

even if the second gateway is matched by marked routing connection?

you can try to mark-routing using chain=output