NAST still being developed / maintained or is now obsolete?

There is a error in NAST that had not been solve since the 2011 (https://simtk.org/forum/message.php?msg_id=6224) and is the same error that I have when I try to run the code with the examples provided in the NASTA folder. Look like the "chem" module doesn't exist.

Anyone can help me. I get the same problem.