Gentlerumps,
we fixed a startup error telling you that you're missing the "Leap Motion Controller" Plugin.
How? By removing the Leap Motion plugin.
Why? Since we're not using it at all. To be honest: we've not even been aware that this has been fully incorporated to the base engine with UE 4.11.x - and now that we've been playing safe on 4.10.x and updated to 4.12.x, we've skipped one subversion and got that thingy sneaky delivered to our workspaces.
On top of that: according to our Engine Editor settings this plugin is completely disabled. Nothing of our game is using that stuff. Not even the compiler, nor the final packager, are complaining about any kind of error. Just a couple of warnings, which we are applying LOVE™ to after all anyway.
But then, a very few of you, who might have ever come in touch with VR (connected your own or friends devices, installed drivers, tried software which installs other unknown things), downloaded our game / update and got a severe startup error. Just due to some plugin and functionality which were not using at all.
Our workaround, for now: we've removed the core engine plugin, recompiled it all and tested it with a user which was suffering that error. He's now online finely checking out the new stuff - so we hope that this fix works for everyone affected out there.
Please use the Steam Community Forums to tell us instantly when you experience any game breaking bug! That's important to every Indie Studio which tries the most, but can't catch all.
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We tried to reproduce this quite a lot - but none of our office or private computers or laptops showed up with that issue. Hard to track, hard to fix. But we got that one, thanks to a responsive community - yay! Skins, Capes, an additional Steam Key and many props out to you, Puma, for being on and available that late for us. :)