Ahhhhhh thanks, I finally got what you mean. ;-) I now looked at my hardware keayboard where the key is that I want to program and then push that button at the same position on the GUI.
Ok, seems I could have saved some time, if I understood earlier how to trick the program to do what I want. But at least I am capable of reading HID codes, using flirc_util commands and some other stuff now. All on the first day using Flirc. :-D
Still hoping for a better layout handling in the future though.