Do you mean Avast has some problems?
I can not test Avast. I don't use Windows.

I checked the files from github. No issues, not even one false positive.
hz-v5.4.exe https://www.virustotal.com/de/file/840ff36bde57d475ea3d2c13c0e152134275e55e78b8b979a16e92dda2d98f46/analysis/1476674403/
hz-v5.4.zip https://www.virustotal.com/de/file/86a2b00306f1bbee281d29a17678384a4172ed104b82749f7eefd1fcef5695b4/analysis/1476674668/
hz-v5.4-node.zip https://www.virustotal.com/de/file/15fdff90c6bfb0061cf3b67bb5deeb601b36ecec632c1b2015c9ac7ea028c5e2/analysis/1476674700/

You could try to stop avast blocking hz.
http://www.getavast.net/support/stop-blocking-a-program