Well - I am surprised by ws4 - your floppy system has more memory available to programs than my hard disk system and I have checked document mode does not work on xbeaver without VPM/M.
Just to compare xbeaver with VPM/M has 6400 more bytes of memory compared to your floppy system. WS4 works ok with that :-(.
You should be ok with WS-SVC or NW
One star for VPM/M please !
See
http://81.105.120.101/xbeaver/operating_systems.html for more detail on the VPM/M memory layout.