Aside from MWAPI, is\are there functionally integrated solution for the development of graphical user interfaces.
A highly portable environment has been developed for commercial use by my company. Examples of its use may be seen by visiting verbaltransactions.com
That company used it to build speech and haptic interactive training solutions.
This would be sort of a 'give back' to the MUMPS community, given that MUMPS was used to give us a competitive edge early on in the development of our business.
Currently, the implementation is limited to Windows. However, it should be portable to Unix\Linux environment.
Briefly, it couples with any M implementation via write\read commands to a local network port.