OK, I downloaded Install Disk Creator and it works just fine. In fact, it was so fast that I didn't know it was done. Which is a problem: function aside, there are not enough indicators showing what's going on, not even a "finished" or "done" button. In other words, this app is incomplete as far as user feedback is concerned. We can hope the developer takes the time to finish the app.
In the meantime, DiskMaker X has plenty of cues and prompts. And it is functionally more complete as well. It sniffs out all and any installers on media in or connected to your computer, including external drives, which is where I happen to keep my installers. It also does a lot better job explaining what's going on, which helps prevent mistakes.
The best that can be said is that Install Disk Creator is a work in progress and has little or nothing to recommend it over DiskMaker X. So three stars is all I can give it, do to the inadequate user interface. We'll see if the developer is up to the challenge or if the negative feedback cools his enthusiasm for the project.