I just made it easier to do this, also for a 'different-armies' collection.
I introduced a new parameter perArmy=1,
which causes the buttons created by including named set commands to appear twice:
one row for selecting the white army, another for selecting the black army.
I made an example of this below. (View in isolation!)
You can view the source code of it by clicking the 'here' link twice,
and then pressing the 'Source Code' button.
Beware though, that you would have to alter 'nocache=true' into 'nocache=17'
(or some other number you never used before),
or you would keep using an old version of the Diagram script that doesn't support this yet.
I just made it easier to do this, also for a 'different-armies' collection. I introduced a new parameter perArmy=1, which causes the buttons created by including named set commands to appear twice: one row for selecting the white army, another for selecting the black army.
I made an example of this below. (View in isolation!) You can view the source code of it by clicking the 'here' link twice, and then pressing the 'Source Code' button. Beware though, that you would have to alter 'nocache=true' into 'nocache=17' (or some other number you never used before), or you would keep using an old version of the Diagram script that doesn't support this yet.