If you're thinking of publishing something unfinished, don't. There's about a 99.9 percent chance you'll never come back to finish it, and it'll probably get taken down. If the storygame you're trying to write feels too long for you to finish right now, go make something smaller, and come back to complete the bigger work when you have the stamina to get through it. Unless your idea of too long falls anywhere under 3,000 words or so. If that's the case, then stick to short, linear stories for awhile before taking on a CYOA.
Other than that, best of luck!