:typesyntax in this manual.
Radio vs. Buttons
Use a radio if you can’t find a good way to describe the item in the choice menu text. I.e. it is better to use a radio if you expect the user would otherwise manually select each item from the choice menu in turn to see what it expands too.
Avoid radios if some of the items expands to complex structures.
I mostly use radios when most of the items are of type
Suggest that the user unhide if hidden, and edit the value directly otherwise.
filewidgets. I think this can be done in SXEmacs by adding a display table to the face.
Add echo and balloon help. You should be able to read the documentation simply by moving the mouse pointer above the name.
Add parent links.