I have been playing with this bug.
Using starting full screen image, the image does appear while monitor is turning.
I am now using Loadmans Mala Speech, and I dont get the error, however I do see a problem that is just as bad as an error.
When choosing bubble bobble and pushing the 1 button 10 times very fast,
Speech says "Bubble Bobble", and the monitor turns horizontal.
The game plays good, but when you exit and are returned to Mala screen,
speech says "Bubble Bobble" and the game starts again, but this time the sound is still playing from the EMU movies, behind the bubble bobble sound.
This action repeats itself 10 times, or the number of times you press the 1 button.
During this time, before the game starts, if you move to another game on the mala screen, bubble bobble (BB) goes ahead and runs, but when you exit BB speech says the new selected game, monitor turns if it is a vertical game, and BB starts again.
I tested this on two other emulators and get the same results.
I think SGT's recommendation may work for this bug, unless Loadman can find the reason it is doing this.