Along with the questions that Yiannis asked,
Give us some information/specs of the device you are using. Esp. how much memory it has installed. We need abit more information then what your have supplied.
Does it work differently when the device is first turned on versus it has been of for some time.
Are you running other programs at the same time(if the answer is yes, does it work the same when those programs are not running.
And that was a good question asked, as to whether or not this same thing happens with other games you have installed on steam,
I also can run this game from steam and it is not slower or faster then using the Launcher directly.
I can access the game from either running a win7 and win 10 computer.
Question #3 from above is most important. Here is the link to the forum page concerning downloading the Launcher.
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