I will attempt to answer easy ones.
History? As in where is it?
Click go and it will show last few sites that you have been to and at the bottom it says "history"
change middle click to open in new window instead of tab.
....I seem to remeber a way to do that in the older build but I can't seem to find it now. =(
If it is any help Control+N is open new window.
open shortcuts in new windows
Open in new window, shift and left click
http://texturizer.net/firebird/mouse.html
Might not help but I tried. I love firebird and love tabbed browseing. To each his own.
Also, make sure to check out the firebird forums because they have the answers when it comes to firebird and are willing to help.
http://forums.mozillazine.org/index.php?c=4