My guess (as a user, not a member of the Esoteric staff) is that such a thing won't be happening any time soon, if at all.
I went through the same issues in my mind before getting my pro license. But, here's what you should consider. They provide quite a few examples to go through and play with. And you can build your own project, but that's not where I think you're going to get the best understanding of what the software is capable of and how it works. The examples really are the thing.
As for the runtimes and how they work, you can get those examples as well. Yes. They are not your project. However, they still provide a really good understanding of exactly how the runtimes work and how well everything transitions from the editor to the game environment.
If you are having a hard time deciding, I can tell you that I looked at just about all of the cheaper options that work with Unity (and other engines, I imagine). There really isn't any comparison. There are differences and bells and whistles (things like mimicking driven keys, etc.) that some of the others might have, but they really don't hold up to the standard of support and quality that Spine has. And the good news is that they keep updating it. Spine isn't going anywhere anytime soon, so far as I can tell. In fact, quite the opposite if the number of companies looking for Spine animators is any indication.
Last, there are tons of videos on YouTube. Once you've gone through the basics, take a look at Erika's twitch streams. Once you see some of the wizard that she demonstrates, I think your decision to purchase will be easy.
I can honestly say that I have zero regrets with this purchase. In about a month and a half, I feel like I am up to speed (for the most part) and am able to produce some real quality game assets.
I hope this helps.