Well that really sucks. I was counting on the ability to resize the image automatically so you don't need to manually resize all your images to specific dimensions. I've tried image=Fl_Shared_Image.get(fileName) followed by image1=image:copy(ts*tc,ts*tc), but that also segfaults. I haven't tried image1:h(ts*tc); image1:w(ts*tc)

Considering getTiles() seems to work only for RGB images, I could try replacing Fl_Shared_Image.get() with Fl_PNG_Image() and others specific to the selected file's type. Perhaps it would do a better job of handling the image, but I'm just speculating.

It seems one or more transparent tiles aren't being added to the table? Another possibility is that removing the image resizing creates a gap between the number of tiles in the interface and the number of tiles in the image.

I wonder if it's possible to dynamically remove transparency from a PNG before resizing it in FLTK. That might solve the whole thing.