Good review. A bit more to RESCUE than described. Here is what I think is going on:

- Search light is colored orange when you first enter castle
- Hits to search loop spot RESCUE letters now (or just hit the letter)
- Completing RESCUE changes Search light to green and lights Break Down Door insert
- Hitting green Search light Locks a virtual ball and plays a cool cut-scene and resets RESCUE, extinguishes Break Down Door, turns search back orange
- Or (instead of Hitting Search) - Hitting Break Down Door starts 2 ball multiball

- Repeat RESCUE sequence, hit Search to lock another ball or choose to Break Down Door

- I was able to Lock 3 balls (virtual), then the next time chose to break down the door.  Game started a 5 ball multiball.
- During multiball, making an Emerald shot causes it to cycle through a few other colors finally stopping on blue. Don't know what happens when you turn them all blue.