When a command in the Queue is processed, it will be removed from the Queue and placed on the Ready list. ZTX37 did its work, now it is your turn to process the results.
Once done, you click the To History button to mark this command as done. It will be taken off the Ready list. Of course you can still access it on the History list, e.g. when you hit the button too fast.
A command will remain on the Ready list until you move it to history. Thus it is essential that you use the To History button.
Redo this lets you re-run the command. You get a dialog in which you can fine-tune the parameters and do another run of either the same command or a modified command.
Generated images have by default a ranking of 0. You can increase that ranking, commonly you would set it to 1, to preserve the image. An image with a ranking above 0, the commands it generated, and the hierarchy of commands that lead to it, all remain preserved.
Each image in ZTX37 is always displayed with a lot of controls around it, on a image display control. Using this control you can fine tune and work on the image or e.g. save it.
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