Need more keys

[TheOlz]

Something must be going wrong for you.
To simplify the process, by copy/pasting and not figuring out the assist and stuff yourself...

Under your Mapped Keys, Combat
Right Click "Assist+Broadcast 1", select Make a Copy.
You will now have a duplicate at the bottom of the list - rename it to whatever (probably "Assist+Broadcast Shift+1")
On the right hand side pane, change the hotkey to whatever you want to press (probably Shift+1) to pass this key to the WoW clients.
Expand the Mapped Key (the little +), expand the Steps (the little +)
On the right hand side pane, under Actions, select the 2nd item which will be "1->All" and change the Key Combination to Shift+1

Make sure to save your settings (ctrl+s), export to Inner Space (ctrl+e) and you should be fine.

If you have changed nothing else from what the basic wizard sets you up with, you will now have a Shift+1 that broadcasts, with an assist before it.
Which it sounds like is all you are after to start with.

As mentioned make sure you don't have shift+1 set anywhere else to broadcast in isBoxer (by default you won't) and have it set to only the action bar spot you want in game (ie. unbound from switching default action bars)

If that doesn't work, it seems like something is going wrong elsewhere, because I quite literally did this as I typed it up on a clean wizard setup and it works fine. If it's a no-go, you're going to need someone more experienced than I am, and it might be worth dropping into the isboxer chat room to see if you can get some assistance there.