🚀 go-pugleaf

I am in the process of getting a very old program running
on a Plus.  The software does not work with 6.0.X so I
figured to boot from a floppy and then run the old program
that is resident on the hard disk.  I tried various old
systems back to 3.x with no luck.

I feel that the problem is that the system is "switching"
on me.  That is when I invoke the old program it starts
up the system on the hard disk, 6.0.4.  I have not
found a definitive reference to how this works with the
various systems, only oblique references to the switching
of systems.  In MacUser, March 1990, page 205, there
is a reference (item 1 on the right) to the switch
ing of systems but this still does not make things
clear.

Can anyone illuminate me?  Thank you in advance.