Rats! (GBC) #Mystery

Starting point: "Start Game" on go
Ending point: Beating level 15 with the giant bull.
Continue: None. 1 is your last life.
          The game saves your password in the password screen but the menu defaults to "Start Game". DO NOT MASH AFTER GAME OVER!
          I've provided you passwords just in case. (The game NEVER tells you which level you are on.) Only use these in the event you lose your password, as lives are stored in passwords.

--- Your Goal ---
Every level has an exit door, but it's locked. You'll have to figure out how it unlock it.
Your HUD will show you when the exit is unlocked.
The final level (with the bull) have an additional requirement.

--- Passwords ---
2. WBM M1D GMFS              9. LKY RDV NLVM
3. LGR 2NV NFGM              10. 4QL 23V ?M8D
4. B5K FXC VHLZ              11. V7F Y7C ZNLN
5. C5K 12F VNMZ              12. CT4 QSD 4J9B
6. 4K2 N7V SKSP              13. 5CZ WRX JJ9X
7. CHC KLD LSRL              14. LLB PGV XRVH
8. CS3 L4D 4FYB              15. C2G B4F B9MG