in order to keymaps and hotstrings to work, you will need at least 2 keymaps... one load to each clone that would like to receive the hotstrings.

for your main, create keymap 1 that has "ctrl-1" mapped to "healme"
add it to the list.
set a description
hit save
name it

now create a new keymap, this one for your clone...
type "healme" under hotstring... and set the key to the key you would want your priest to hit when this hotstring comes through... like the '1' key
add it to the list.
set a description
hit save
name it

hit ok on the setup dialog.

now, you can either add the keymaps to the wow command you create or right click on each clone and load the map manually.

once you do that, hitting ctrl-1 in your main will hit '1' in your clone and vice-versa

have fun!