I think you can set any shortcuts you want in the keys file (copy the keys, preferences, menu, toolbar, etc. from /usr/share/icewm/ to ~/.icewm/ and modify the keys file), but that might be just for launching apps (I'm not sure). However, I know several of those options are available in the preferences file in the same directory (It's quite a large file -- you'll have to go through it manually. You can grep for the term and then edit it using a text editor with search capability if you want). I know the preferences file has keybinding options for Maximize, Minimize and Move and may have more options. Also, for an easy cheat, Alt+Space brings up a menu with all of these options with shortcut keys, so if you don't want to fiddle with the preferences file you can always press, for example, Alt+Space and then X to maximize.
