To support "point gun at joey": you can't use a built-in verb since you want to have a preposition. Do this instead:
1) Click on Verbs in the left Pane. Then click "Add".
2) Set the command pattern to:
point #object#
Set the attribute to:
pointat
(It doesn't have to be that, but call it something related. "pointat" works well enough.)
3) Under the section "Multiple objects" further down the page, set "Object separator" to:
at
4) Set "Menu caption" to:
At which object?
This probably won't kick in, since it only does if there are multiple objects nearby that the verb applies to.
5) You can also set default text if you wish.
Now...
6) Select the gun. Click on its "Verbs" tab.
7) Click "Add". Scroll down in the list to find the "point" verb. For me, it was at the very bottom. Click OK.
8 ) Where it says "Print a message", change it to "Require another object".
9) In the new empty list that appears, click Add.
10) Pick Joey from the list and click OK.
11) Add whatever script you wish for when the gun is pointed at Joey. (Perhaps just print a message to begin with, to make sure it works.) You can always come back later and edit the script.
That worked for me. I could then enter "point gun at Joey", and it would run the script. Let me know if you have any problems. It might seem complicated at first, but the main trick is that you need to define your own verb first and give it the "at" separator. Then you can apply it as usual.