I tried to use HeavyMetal v3.1.003 executable (from http://www.albinarrate.com/heavymetal/releases/HeavyMetal.3.1.003-EXE.zip)  with John Nagle's ttyloopdriver, but it refuses to open the port.

I get the following message when the software initializes:

"invalid COMMPROP block length= 66 at script/heavymetal.pl line 4582"

This happens on two different PCs, both running Windows 10.  

Anyone experienced this before?