During the phase I testing (one widget for one template) of the ROIRemoveAll
widget the following things were noted.

The "Image=..." button image is displayed, however when the mouse clicks or
hovers over the button none of the other image buttons are displayed, from
"ImageHover=.." and ImageSelected=..." 

I realize the reason for this could be that the widget is not functional, but
this is not consistent with many other widgets. The point of this bug is really
to think about what should be displayed when a button widget is not functional. 

Option 1: We could add another Image parameter that tells the user that it is
currently not active, eg. a grayed out image. If in debug mode display warning
in the the error popup widget.

Option 2: Only display the "Image=..." button to and when the user clicks or
hovers over the button nothing changes to the button. If the user clicks the
button a Warning should be displayed.

Option 3: Have the parameter’s "Image=.." "ImageHover=.." and "ImageSelected=.."
working, when the user interacts with the button. If the user clicks the button
a Warning should be displayed.  

My vote would be for Option 1 or 3. Option 3 is the one most commonly found in
widgets.