Adding a new [custom] application launcher to the panel is easy. However many users want to use a special icon for that application and thus trying assign a new  icon via the (i guess it is called) icon browser. So the browse and finally find the appropriate folder, but all [icon] files are grayed out. 

Some smart guys of my GNOME1 to GNOME2 migration testers found out, that they need to select a folder. But even doing that, 99% were not able to assign a new icon, because they did not find out about the very "unique" behavior, that even if a directory is selected, the have to point to the combobox and have to hit the <enter> key.

So RFE:
1) If a users browses an icon folder, it should be able to pickup the icon directly via file (usually the user already knows its name).
2) If a user selects a directory, the "thumbnail" window below the combobx should update its content immediately so that the user may see all available icons and pick one up without any other frustration!