There's no such thing as "cheating" with chords.  Chords aren't "owned" by anyone in particular.  And unless you completely copy (plagiarize) someone's chord progressions and instruments in a song, I hardly think cheating is possible.  If you're using Cthulhu on your own, there is no way you can cheat. 

I wouldn't say there's much anything anymore in music that counts as cheating except just straight up stealing someone else's songs.but as for this, I think it's just more lazy. I feel if you're actually trying to be really into this, you should put in the time to learn music theory, or at least the basics. Maybe using this isn't that bad (I've never used it, I don't know how it flows), but you can probably understand it and do even better if you know music theory. Relying on not having the knowledge to do something can really hold you back when it comes to other times. That's at least my opinion. :/

Cthulhu doesn't magically give you a chord progression, it just gives you options that (kind of) sound good together. I use it sometimes. I also use one called J74 Progressive that is even more like "cheating" -- I can just choose a scale and choose among common chord progressions with a drop-down, then modify it to my liking. I like that one better because it has helped me learn music theory in much the same way that Cthulhu helped me avoid learning it.

But I hate it when anyone calls anything in music "cheating". Fortunately nobody here is calling it that. Is sampling cheating? Is using loops cheating? Using presets? Using chord-helper software? Hiring a vocalist instead of singing? Hiring a sound designer? Using a DAW instead of playing live? Using VSTs instead of hardware? I have a guitar I made myself, does that mean you're cheating if you use one you bought in a store?

Cheating requires rules. You can't cheat if there are no rules. There are a few -- like copyright law. Beyond that, if you're making music you're making music. Do whatever works for you. If you like the way it sounds, and someone else on earth likes the way it sounds... it's music. The rest is just pedantry.

So this really reminds me of Odesi by Mixed In Key. Great tool for understanding chord progressions if you are a "visual" learner. For me, I'm not that great with reading things I don't fully understand.

Definitely would look at this as tool, not cheating. I think this can help when you hit that inevitable producer/writers block.

I saw the dilema too, so I draw the line right behind that chord generating section. That section I tend to not use. That apeggio part though... It's simply best arpeggiator on the planet. ...though I usually record midi output of it anyway and do some little edits to the result.

I use autochords.com sometimes when starting songs.