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I searched the forums and haven't seen this.

We opened an item to print, added a second item in Matter Control, but when we clicked on print, it only printed the original item, not the second item.
I can't seem to find the step we must be missing.

In thinking about the problem, it also had me wondering, when adding multiple items to print at the same time, is there anything special that needs be done to make sure it doesn't print one item at a time?

What happened is it added it to a queue, and it will print them one at a time as you noticed. Instead, to print multiple items at once, click edit, then insert, then select your file.

I didn't describe it correctly, you are correct.

We did use edit and insert- my mistake. We could see both item in the preview screen on the right, even moved them to the sides so there was enough room in between them for the skirts.

To answer it, apparently we didn't save the file after adding the item. We have it working now.