Hi @vtpup
There is another, probably, way:
Download the ISO or IMG of your choice (15MB -23MB)
That file allows you to creates a bootable on USB or CD
Add your PUPm DOG, and Ubuntu ISO file(s) of your choice to the "/boot-isos" folder
Boot and run any PUP ISO files you added.
The IMG files I made, for this thread's opening post, intends to be easier for many/most new members.
Let's us know if you have any issues.