HI,
Thank you for your interest in Ornatrix. You can learn Ornatrix in one week, even in a day if you have enough experience with 3dsMax and other hair tools. Ornatrix is pretty simple to learn because it uses a procedural approach just the like modifiers in Max and we have a lot of tutorials in our Youtube channel. I suggest you take a look into our Ornatrix 101 playlist. Ornatrix does support Octane but there isn't any One Click hair solution, Ornatrix have a button to add hair to a model but that's just a basic preset to start grooming.
The best way to see if Ornatrix is the propper tool for your approach is to give it a try and whatch our tutorials, of course, we are always here if you have any question or technical issue.
Regarding the mesh disappearing problem, I will take a look into your scene in the morning and let you know what's the problem is. Thank you.