200101 SPAW editor custom button

I want a custom button in SPAW editor ([login to view URL]) The button has to directly open a screen where the file (pdf) can be selected (certain directory, show *.pdf or *.*) or uploaded. Using SPAW_FM is fine. When the file is uploaded/selected the button OK has to return to the editor, enter a standard text with a link tag to the selected PDF. So basically I want a simple way to insert a link to a pdf (with upload option).