The file mx.exe is the binary that you need to grab to run mx on your VAX VMS
machine.  It was compiled under VMS 5.4 on a VAX 6440 on November 30, 1994.
You can use the DCL utility mx.com to run it.  The utility will complain in
the quite likely event that you don't have enough pagefile quota
to run Mx.  I recommend that you check this out before you want to use it.
The use of mx.com is described in the manual which is available in
postscript format or if you would like a bound version please send $25 to
cover copying and handling.

The file imx.com may be used for interactive editing of input scripts.  
In conjunction with the following line in one's login.com
$ define MX_EDIT eve
it will use eve (or another editor of your choice) to view the input and 
output files.  If there is an error, the cursor is placed in the upper 
window in the input script at the place the error occurred.  If Mx runs 
successfully, the cursor is placed in the bottom window at the end of the 
output file.  The multi-windowing facility is only available with eve, I 
think.  Thanks to John Fritz of MCV Health Sciences Computing for 
assistance with this development.

See the directory ~ftp/pub/mx/examples for example files.