I prefer not to remix decks, but the way i do it is to; 1. Record a video Up to 29 seconds. 2. Edit it if you want it shorter. 3. Then go into Castle, and into a specific deck. 4. Make an actor and go in to the responses. 5. Select "When this is created", then "Play sound", and then "From file". 6. Select the file from your galleri and paste it in the sound response 7. Modify the speed and volume if you want. 8. There you go! (Sorry if i mislead you)