There might be some guy having the same issue as you, I forwarded their case to the devs, it might be fixed in the next days.
I do not forward your case because you can not find any error infos (yet). But if you can manage to find any error reports (about your question, the error report should be a .txt files or something like that, the only one on your installation directory).
And also, check your windows event log by typing Event Viewer into the start menu and look for the applications log.
If something went wrong with starting up Reus (likely) it will be logged there.
Then copy/paste the error reported !
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