You can combine all tiles you want. the used style for creating the tiles makes no matter. The restriction is : resulting gmapsupp.img can have only 1 fid and can use only 1 typfile. if you try this, the minimum options are :
family-id=900
product-id=1
code-page=1252
family-name=your name
series-name=your name
overview-mapname=anywhat
area-name=your area
gmapsupp

#list of used tiles:
6324*.img 789*.img 8910*.img  and so on.....

By the way : only gmaptool can create a gmapsupp from different <name>-gmapsupp.img as source.
thomas