I was trying to improve on the duckduckgo icon (the original one being the favicon from the site, I was trying to make a new one using Screenshot captor.)
I was using Paint.net and an addon for .ico.. and I was experimenting with multiple sizes in the source file (including an odd suggestion of 121x121 which was the same size as the original image). Then I decided I only needed 64x64 or 32x32 and tried those. At some point FARR seemed to decide to display a generic icon for every alias, whether it was Core or MyCustom. I double checked the aliases to make sure I didn't do something besides creating a new image, like screw up the icon path. I restarted FARR, deleted the Windows icon cache, restored an older copy of FindAndRunRobot.ini from 4 hours ago, deleted the duckduckgo.ico file, and rebooted, so I am not sure what else to try to get FARR to display alias icons again.