I've tried:
hgroup [label "Note" 64 AFV_Note: area 100x50]
That produces the correct width but the height is still too tall.
I also tried:
hgroup [label "Note" 64 AFV_Note: area options [init-size: 100x50]]
That results in an error; probably not an option for 'area'.
Does this help at all?
https://github.com/gchiu/RSOChat/blob/master/rsochat.r3#L811