Set attribute 1 of the MVOB file item SPEC to the correct 2a system type identifier from the list OR create your own new set of subroutines with a new type.
You can use the screen SPCMAN to set up these system parameters once the MVtools have been properly installed.
The 2 alpha code for each MV database is used internally by MVtools to identify the system you are using and effects the behaviour of MVtools.