Screenshot creation in Doors NG
One answer
No, there isn't. It's not quite the same, but one thing I do frequently is use a screen capture tool that automatically saves the captures as files, and then drag those into the module. If you're using the text editor, you can paste an image from the clipboard so you don't even need the step of finding the file and dragging it.
Feel free to open an enhancement request... I think it would be nice to be able to add items to the module directly from the clipboard (and that's probably easier to do than adding a screen capture tool to DNG).