Hi Gianni, because of the special nature of header and trailer frames which do not provide field expansion on printing, there are a couple of triggers NOT available on Header/Trailerframe since the very early days. Unfortunately, it looks like you can not paint an inner entity in the header frame. So the only(?) option for a talented exportfile editor with a sound backup concept is to convert header frames in the export to a "normal" entity. Change the frame type in FORMPIC and rename UXGROUP/UXFIELD away from HEADER.USYS.

Thanks Uli! Effectively it's probably my first DropDownList in an header... I solved with a small edit session on exported form... :-) Gianni P.S. Definable as [SOLVED]