I can't test it, and I don't remember whether you can do that or not; however, see whether it is possible to conditionally display the button using SET_ITEM_PROPERTY. Something like this:if :system.last_record = 'TRUE' then
set_item_property('your_button', displayed, property_true);
else
set_item_property('your_button', displayed, property_false);
end if;
Or, perhaps the VISIBLE property should be used (note that you might need to modify ENABLED, NAVIGABLE and some more properties when making it visible - it is described in Forms Help so - have a look).