Custom palette with images doesn't show the images
I created a new palette for holding custom images I'm using in my scores.
I based my self on the chapter of the handbook for creating oassia.
I've added 2 images: one .SVG, one .JPG.
Both are present in the palette but with NO THUMBNAIL.
I've tried to enlarge the palette cells, without success.
In attachment, the 2 images.
How to solve this ?