I noticed the main reason that you cant get the dialog to do anything. You initially called the dialog "awaysys", but then you call it "away" every place else.
I have a tendency not to use the same names as commands used by mIRC. This helps save my getting more confused than normal. But, that's just me.
You'll find a few other errors here and there as you continue your testing. Example: dialog ID 17 (Reason) will show on all tab definitions unless you put a tab 1 at the end of that line.
Also, if you use .amsg to announce your 'away' status then you wont see it going out to everyone else. I normally use /amsg in the remote section so that I can see it as well.
But it's a good start so keep plugging away. Hope that this helps.
Listner