2B45F | $05:B25F | 1 byte | Misc. | X-Length of Message Box window. | Ice Man
2B462 | $05:B262 | 1 byte | Misc. | X-Position of Message Box window. | Ice Man
The 1st one is a length of the messagebox, but it behaves weirdly. You should find out why and submit it with a better description.
The second one isn't the x position. It rather stretches the messagebox so there's something up with it. Perhaps the border x position?
You should analyze them a bit more, as they are related to each other in some way. My guess is that they are something like 'x position of left border' and 'x position of right border'.
. I could post stuff now and then
My Assembly for the SNES
tutorial (it's actually finished now!)