Short answer, Ctrl/Alt f1-f6 only work when you're playing with Windower.

Longer answer, <stal> won't let you f1-f6 people. You have to scroll up/down with the arrow keys/dpad, but it's significantly faster than tab-targetting regardless. The starting position of your <stal> arrow also depends on your current target (defaulting to yourself), so you can get a head start that way.