I got the installer working (the sh command gave a syntax error about ")" or something) but the second one worked. Where IS my 1.1 install though? I couldn't find it where you said the default would be, and I don't see any way to locate it. How do you locate things on the HD? (I am SUCH a noob.)
try /user/share/games
you might need to chown the folder to your username. i keep a shortcut to my trem folder for easy map download and to quickly launch.
as for catalyst: i'd have most things set to application controlled (be sure to turn catalyst AI on, i have no clue why it is set off by default.
you should be able to avoid the screen ID (the red box with the 1) if you log out/restart and then launch trem without opening the CCC.
if that does not work, you can always open the CCC first, launch trem, alt+enter to switch to windowed, click the screen id toggle button, switch back to trem and alt+enter for fullscreen again.
if you can get http download working, let me know. i always get a libcurl error (despite having the correct libcurl installed) and have to alt tab out to manually download maps.