What are you interested in Vanya? Would you like to make a CV1 like game in this editor? I am sure it would be way easier to work with SC4ed to rebuild metroid like CV1 then using the original game. Programing something like a key would be easy. The door does exits you can check out the bloody crusade hack to see how this looks.
Redguy did make a good randomizer for this game:
https://www.dropbox.com/s/pnci0e3t9rl9mgf/SCV4Randomizer.exe?dl=0If you like you can go and watch bobby playing it.
https://youtu.be/mdZbtsIxx1Y?t=104I don't see anyone who would like/is able work more on it.
The uncensored hack seems one of the worst hacks done. You could just play the Japanese version and not suffer for extra loading time on each screen. May be make a translation instead? Are you concerned not to be able to read the title screen? I think the kanji title with the castle looks awesome. Sure with some effort this could be done but why do you want this so bad in the first place. Why would you go through effort of patching to see a other title? Just something I don't understand the effort it needs.
Beside if you think about fixing the uncensored hack the title screen is hardcoded so it will take some research to get it done. Not sure how good you are at disassemble and document the code good enough to make the desired changes. Once you found a good hijack it might not be to bad. Personally I would skip the research and code it from scratch. Look for the assembly tables in the J version. Get a idea how the event timers are. Update the Xpos Ypos and assembly pointers. Decrease the Ypos for the drop till the bottom and reset the routine.
update: ;related code for the drip in the J version
org $03DBC4
JSR $DD01 ; initiate blood drip?? Event at RAM $780
org $03DD3C
JSL $02D65F ; blood drip routine
org $02D65F
LDA $22,X
BNE $02D682
LDA $24,X
ASL
ASL
CLC
ADC $00
TAY
LDA $0000,Y
BEQ $02D685
CMP #$FFFF
BNE $02D679
STZ $24,X
BRA $02D663
STA $00,X
LDA $0002,Y
STA $22,X
INC $24,X
DEC $22,X
RTL