Backtalk interpreter access

Dec 14 04:23 UTC 2017

Reading the documentation for the Backtalk system 
(http://www.unixpapa.com/backtalk/stab/doc/), I see the conference 
system is build on top of an interpreter for its own programming 
language, which is similar to Postscript or Forth.

Is the interpreter accessible to ordinary users, either inside Backtalk 
or from the Grex shell? Can Backtalk Script Language be used to create 
our own BBS customizations, or general programs?