I have noticed that, when importing Objects and Widgets, some of the icons are missing. I've opened the folder where these are kept and see there is a thumbnails folder with all the icons. Only, some are there and others aren't. I have figured out that in some cases I can create a new image by importing an object, deleting the file from the folder, then exporting the object back into the folder. But this doesn't always work. This is driving me nuts! What am I doing wrong?