eric i really am struggling with this. i cannot see a show/hide layer in client validation.
if i click my checkbox then client validation it asks me which form, then the element which i can only choose a specific filed not the whole div section so i assume i choose the checkbox here.
after that i used the server behaviour utilities, show region utility on the div, i set the checkbox = value "2ndapp" which is the value of the checkbox.
i am not sure where to now i do not seem to have the options you are saying. i have latest css form builder installed.