As I said NEVER, but maybe I wasn't clear enough... ... ... I played it though!
The windows unrecognised warning really shouldn't stop you opening indie software.
Though you shouldn't need the warning to use an anti-virus (I still can't believe I'm gonna say this but windows defender should do the job), and anti-malware is always a good idea. Always scan anything you download, it won't eliminate the risk of new/fancy malware but what's life without risk management (Backups! Make like 60% of your life about backups, probably the best advice I can offer).
I won't explicitly tell you to launch the exe (that's for you to decide) but do play the game, short for now but very very sweet
Sorry for the long text but computer security can be summed up as the great Robert H. Morris Sr. said : "The three golden rules to ensure computer security are: do not own a computer; do not power it on; and do not use it." He was a computer scientist that work for Bell labs and the NSA, I believe he didn't follow those rules