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Ahhh! It finally worked again.  I don't know what command finally did the trick but a pop-up 
"Running wine-unity3d-installer" finally appeared and now the game loads.

First I did the command you recommended:

sudo pipelight-plugin --create-mozilla-plugins

I tried switching different browsers through the UserAgent and ran these commands again:

sudo pipelight-plugin --update

sudo pipelight-plugin --enable unity3d

So is there a specific order to run these so it will work first time?

It totally works!

I got Dead Frontier to run in Mint 17 and on my Chromebook with Ubuntu 12.04

Its kinda slow on the chromebook, but it runs!
Thanks for your help