When using Windows, how do I press CRTL, ALT, DEL or other multi-key strokes?

You can do this in one of two ways. You could type the character sequence CTRL-ALT-DEL-ALT-CTRL. This turns on CTRL and ALT modes, puts in the DEL character, and then turns off CTRL and ALT modes.
Or, you can type the orbiTouch’s special “CTRL ALT DEL” character — this single character is shown on the Slide Guide.