Login to Signals Image Artist and load the data in question, make sure to select the Browse view.
Now right click to reveal the SImA context menu, here you will see the option to download the image as shown below:
When using a supported browser e.g. Chrome, you can double right click on the image whilst in the Browse view to reveal the browsers own context menu, this menu will have additional options e.g. "Copy image", "Save Image as" etc.