button and Group (which button is extended from) don't have a focusPercent field, afaik.
You could do this;
In your .brs script, add an observer to the button's focusedChild:...
m.button.observeField("focusedChild", "focusChanged")
...
sub focusChanged()
if m.button.hasFocus()
' the button has focus, decorate accordingly'
else
' the button lost focus, undecorate accordingly'
end if
end sub
Actually you probably need to use "m.top" instead of "m.button" assuming this script is in the actual button brs.
aspiring