Embarrasing Fact: Power suit made by lowest bidder
As I said before, Samus's position on screen is NOT changed when she enters a door, and the screen she appears on is fixed. Then Samus moves a set distance in the direction of the door during the scrolling.
So when you enter the room with the grey door, you'll appear in the screen above the door to the room you just came from, then move down a rather large amount (I'd estimate 1/2 a screen). So the places you can end up in the room with the grey door are limited to the top half of the screen with the door you enter from, and the bottom half of the screen above that. Virtually a dead end.
HOWEVER, the door you WANT to enter is on the far left of the room. Which means that it will also be one block up and right past the right edge of the room (see the OOR travel explanation for why). So you just need to be near the middle of the far right edge on the bottom-right screen so you can touch that door.
Since Samus's position on screen isn't changed when you enter a door, except it's moved in the direction of the door you entered, you can figure out where on a screen Samus has to start from to get to the position you want. In this case, you need to hit a door block while on the very far right edge of a screen, and relatively low on the screen (within about 3 blocks of the bottom).
And for reference, again, each 16x16 group of blocks = 1 screen = 1 map tile.
So when you enter the room with the grey door, you'll appear in the screen above the door to the room you just came from, then move down a rather large amount (I'd estimate 1/2 a screen). So the places you can end up in the room with the grey door are limited to the top half of the screen with the door you enter from, and the bottom half of the screen above that. Virtually a dead end.
HOWEVER, the door you WANT to enter is on the far left of the room. Which means that it will also be one block up and right past the right edge of the room (see the OOR travel explanation for why). So you just need to be near the middle of the far right edge on the bottom-right screen so you can touch that door.
Since Samus's position on screen isn't changed when you enter a door, except it's moved in the direction of the door you entered, you can figure out where on a screen Samus has to start from to get to the position you want. In this case, you need to hit a door block while on the very far right edge of a screen, and relatively low on the screen (within about 3 blocks of the bottom).
And for reference, again, each 16x16 group of blocks = 1 screen = 1 map tile.