If we add a text file in a container, FileMaker shows the icon.
But via plugin I can add a JPEG to the same container and FileMaker could show the picture.
This is actually what we do for PDF files (include JPEG preview), so FileMaker can show the JPEG on Windows.
(same for TIFF or BMP files).
So the attached database should show the image twice and not the icon.
The output container does contain all required pieces: DPI_, FILE, FNAM, JPEG, SIZE