Prevent dock stacking First of all, I'm quite new to mac so sorry if this question is too obvious. I'm coming straight from Arch Linux, so this is still a bit confusing for me ;-)

I have problems with the dock. It seem to group windows but always shows the most on top icon. Is there a way I can have mac simply show all available windows?
I.e I have the Mail Application open, and it seems there are 3 windows: 1 Message composition, one detailed view of a message and 1 message overview window. I seem to be able to see them only if I swipe up with 3 fingers and then I get a overview where the 3 ones are on top of each other with every one overlapping a little bit. Also with cmd-tab I can just open to most recent window.
What is the standard way to navigate between these windows?
You can use  Cmd ⌘   `   (the key under escape) to switch between the windows of an application.