Just to confirm, are these the steps you were following to create the bootable ISO - https://dell.to/2PkSmPY ?
Can you let me know anything other specifics you may see? As well as at what point you see the error appear.
I'm having the same issue. The SUU ISO creates fine but SmartBootable does not. It fails about 10 seconds after starting, doesn't progress from 0% and does not create a file. I am following the steps in the link posted above.
When I originally added the package to the repo I only selected the OS Independent option. I went back and also selected the Linux option and was able to create the SmartBootable ISO.