Hi everyone,
Unfortunately, this bug still exists in Spine v.3.4. I experience the same behavior i.e. Spine downloading its latest version every time it's launched. Just from a usability perspective, I personally don't mind, but it's annoying, and as stated before, might be an inconvenience for people with limited bandwidth etc. So I'm just letting the Spine team know.
As a side note, I'm a software developer myself - and since this issue happens every time on my machine - if there's anything I could do to investigate the issue further, please let me know. And what I mean by that will probably involve something along the lines of bytecode debugging etc. but that's reverse engineering and I most certainly would not do that without Esoteric Software's explicit permission.
Anyway, keep up the good work.