HI, I think I see what you are wanting.
I made use of standard nodes to create the required rows based on the input address range, and then used a java snippet to create the actual IP address for each row.
And just for giggles, packaged something very similar up into a component…
Here is the workflow.
Ip Range Loop.knwf (43.3 KB)
The component has also been uploaded to the hub, and can be pulled in from here:
I hope that helps!