... Okdidoki, I tried (using Crazy Fairies as my playground), and am giving up again for now.
I can't get Unity Player to work, neither in Firefox (nor it with all add-ons disabled), nor in Internet Explorer.
In Firefox, I got to download and install the player again; then, tweaking some bells & whistles and/or trying without add-ons, I get no further than an error message "Failed to start Unity Player." That screen meanwhile suggests clearing cache and retrying, which of course does nothing.
In IE, which shouldn't be blocking much of anything at my end, upon getting to the Crazy Fairies main page, the "lay" button there does nothing at all. Trying the Windows installer there (and expecting it to trigger the installer again), rather than attempting to install Unity Player, what it wants to run is what looks to be some Crazy Fairies installer. I don't usually do, by default; and either way, my guess is it's not what we're looking for: Presumably that would be some standalone donwloadable game version. Correct? And anyhows, if all of their games require a separate installer for each game, that could be argued to be a bit much; indeed I don't personally feel tempted to.
Checking their forums on the matter typically leads one to no results, or unhelpful ones ("uninstall all you've got & try again" -- down to a Windows reinstall, sure baby. Or right-click the Player content to go to your settings -- very helpful if you can't get to that content. Never to worry, I did get to those settings -- featuring nought but a cache control page, which is duly set to on as it should be, so that can't be it, either. What is annoying is that there is no further control panel or anything for it, or not as far as I can see.)
Oh well, so I won't be playing no Unity games for the foreseeable future, it arguably is no skin off my back, I've gotten along fine without it before.
Strangely, I can run some of their demo material at http://unity3d.com/gallery/demos/live-demos -- although trying to play in one crashed my machine, LOL. Yes, yes, that's probably just my machine not being up to speed, whatever.
Just one more reason why Chrome is the bestest.
Yes, well, and in all friendliness, but I wouldn't consider one's program working just in one browser a point of pride; rather of course, it should preferably work on all platforms, or as many as possible.
Re: the link, if any, between Google Chrome and Unity Player, this thread in their forum should be of interest: http://forum.unity3d.com/threads/202063-No-more-web-player-support-in-chrome-and-firefox , spawned by this article: http://blog.chromium.org/2013/09/saying-goodbye-to-our-old-friend-npapi.html .
Another annoyance of course would be that all the documentation on their site is heavily tilted towards developers, not end users of their Player.
Again: It really isn't much of a bother to me, and neither is this any sort of attack on you, Tass (why would I); but if these critical remarks somehow spill over to the Unity crew, then fine.
If anyone can add to how they get it to work at their end, or what we're doing wrong or where we have our heads up the wrong end, then please go ahead.
Cheers.