Any problems with using Ctrl+Shift+F12 to put the display to sleep? It won't work for some reason but Ctrl+CMD+F12 for system sleep, Ctrl+F12 sleep/restart/shutdown box, and just F12 for eject works.
Open System Preferences->International and in there select the mini-tab 'Input Sources'. In there put a check mark in 'Keyboard & Character Viewer' and also in the flag of your country. Then that flag will appear in your finder menu bar. Select that Flag and in the drop-down select 'Show Keyboard Viewer'. This way you can see when you press a key you will what OS X sees the key as.
Open System Preferences->International and in there select the mini-tab 'Input Sources'. In there put a check mark in 'Keyboard & Character Viewer' and also in the flag of your country. Then that flag will appear in your finder menu bar. Select that Flag and in the drop-down select 'Show Keyboard Viewer'. This way you can see when you press a key you will what OS X sees the key as.
I did that. It does register the keystrokes, so I'm not sure why OSX isn't responding to it. It worked before with Lion (my iMac came with Lion preinstalled), but I reinstalled Lion and now it won't work. Works fine with the Apple Wireless Keyboard though.
Wirelessly posted (iPhone 4: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)
I use a Logitech G19 keyboard and all of the keyboard shortcuts you named work fine for me.
Wirelessly posted (iPhone 4: Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5)
I use a Logitech G19 keyboard and all of the keyboard shortcuts you named work fine for me.