MIDI Target Manufacturer(s):
I did a search on this, and it appears that the problem is occurring because the only place from which we can pull images into the image manager is the photo gallery.
I screen-shotted images from the desktop app that I'm hoping to control, modified the images to change the white opaque background to transparent, then saved the file as a .PNG. I then saved the file to my iCloud drive, then opened it from the iPad, and saved it to my photos. The posts here suggest that Apple is removing the transparent background somewhere in this process, and that may be why I'm having trouble, but I'm unclear exactly how to work around this.
I think that there may be another way to get the images into my photos, but not sure what method to use, and which one will keep the transparent background.