Normally, the red x over an image indicates that the image has been referenced in a topic, but isn't being found on disk. Perhaps someone deleted it.
As for the green check mark, I believe these are related to using the image in conjunction with the Resource Manager. I believe the green check mark is an indication that the image is in sync with the copy of the image in the location specified by the Resource Manager.
Unless something exists in the help documents somewhere, I'm unaware of any table or cross reference for what the icon images mean. Sorry
For me, the help system for Adobe products is nearly unusable. I much preferred it when they offered CHM help. But I'm a lonely voice.
Thanks for your reply. I also find the help system of almost no help. It explains topics but only from the perspective of someone very familiar with the program .
I'm unaware of the uses of the Resource Manager--should I be using it? Seems strange that only those 3 images have the connection with Resource Manager.
I find it very odd that you would have no knowledge of the Resource Manager, yet be using images that are part of that aspect.
Is this by chance a project you inherited and are now responsible for maintaining? Or is it a project you personally created?
If you personally created it, is it a project that was created by using a template or did it begin life as a blank project?
For what it's worth, I just tested by adding an image from the Resource Manager and it looks identical to your sample. So it would appear my interpretation was correct.