when i stared to download, my browser would tell me that the binary-waterfall.exe couldn't be open, why's my browser suspecting this as a virus?? i'm completely confused.
I didn't have this issue. If you have an antivirus you should turn it off, or even get rid of it (unless it is Windows Defender). If all you have is Defender, go into its settings and un-quarantine the file
It's 100% not a virus. A lot of antivirus software give false positives.
90% of anti virus software are gonna mark any exe files that dont come from either official or paid for sources, an exe without a publisher that it can recognize is guaranteed to give a positive, false or not. just make sure you actually trust what you download before you run it