The image you copy is the image you see, if it is disabled, it is a dimmed image.
If you want to copy an icon that you have setup with the Icon Chooser, use this process:
- Double click the source icon to display the Icon Chooser with the icon preconfigured.
- Select the target macro.
- Click (once) the macro icon to select the image well
- Click on the icon in the Icon Chooser to set the macro icon
As noted by @JMichaelTX, as well as actually working regardless of the enable state, this will result in the icon being stored in a very compressed state (basically just a few bytes with the details of how the icon is constructed) instead of as an image.