Hi arlo,
just by trying again this morning, I've found out, how it works!
Just let me explain for those ones, who have the same problem:
Connect your iPad with the Alesis iODock II. Then open Set List Maker. After that, open Midi Bridge.
In Midi Bridge go to the "Interfaces" tab. There you should see at least the io Dock, MidiBridge and SetListMaker In's and Out's. Connect the
iODock In with the
MidiBridge Out.

Than tab the Modules icon in the iODock In. There make the checkmark to Stream Byter and than tap the i-icon to open the Stream Byter settings.

In the text field of the preset settings, type the follow:
B0 0E = B0 50 7F #(where the 0 is a Zero!)
After that press "Install Rules"

Now save this preset while tapping the white arrow above to name this preset. (A name like you want) And than press Done in the left upper corner. Press Done again to come back to the "Interfaces" tab.

After that, you should save the Scene. To do so, press the "Scenes" Button and hold a scene for 3 seconds. Now you can name your scene and than press the Save Button.

Okay, thats the settings for MidiBridge.
Now go to Set List Maker.
Choose Settings > Remote Control and scroll down to MIDI-channel.
There you choose "MidiBridge" In the Port-section and (maybe) Channel 1 in the Channel section.
After that scroll down to the MIDI-Controllers and choose for "General Purpose Button 1" maybe "start/stop audio 1"

Now go back to your shows, choose the set you want and choose a song with a playback in audio 1 and hit your footswitch, who is plugged to the Alesis iODock II.
Thats all!
Hope you'll find this helpfull.
Thanks for watching
Kind regards
--Elle--