Wolfram Player Pro is a low cost desktop application deployment solution for Mathematica Notebooks. It is "read only" w.r.t. new command lines, but end users can of course input data via Graphical User Interface (GUI) form elements. It supports truly rapid development GUIs that hide all of the complexity of the Wolfram Language.
As part of a long term project developed, initially during work for a client, Webel IT Australia in partnership with GreenSoft Pty Ltd is developing a very complex Mathematica application with substantial SysML modelling support.
There are a number of ways of simulating and executing various aspects of Systems Modeling Language v1 (SysML®), and they are not just novelties! They also really help your models become more robust, logical, and organised.
There is "internal" tool simulation of Activities and StateMachines based on fUML (or variations of it).