Dear Naomi,
Changing database type can be accomplished by a two-step process.
First, export the current database as Standard Format. (All this does
is to strip off the first line or two which are Toolbox-specific and
which include the database type.)
Next, open the file in Toolbox. Since the database type is gone,
Toolbox will take you to the Import dialog box and you can select the
database type you want.
Note, however, that the alternate hierarchy has the sense number in a
different order than in the standard hierarchy. You may need to move
that field. I can help you do so if you have a lot of entries.
Toolbox Support