Keep secure traffic on ONE gateway?

RouterOS General
1

I think Policy based routing would do the trick, I’ve got some links to HowTos in this forum if a search doesn’t turn them up

2

flow marking in mangle and policy routing should do the trick.

3

Here you are:
http://www.mikrotik.com/docs/ros/2.9/ip/route
And example:
http://www.mikrotik.com/docs/ros/2.9/ip/route.content#8.48.3.2

4

Might want to look here too:

http://www.mikrotik.com/docs/ros/2.9/ip/mangle

Look for “src-port” or “dst-port”.

~ Jason