Title pretty much sums up the issue. Tried to install from my library, from the store, nothing - I click the install button, a window pops up and nothing happens. Not very nice…
Hey man, I had the same issue and to solve it, just download the game from the Microsoft Store. It should be under Libray (left bottom of the screen) and then Games (on the top). After this select FH3 and on the right side there will be a download button. After it installs, it will show up in the Xbox App and you can play it from there. I hope it helps.