...Well, I should have tested it before I said so.

This happens now: https://www.dropbox.com/s/whqk8jbo8ei7619/Screenshot%202016-12-09%2010.07.01.png


Fixed it with this unsavoury method, but, :l

repl_020BD2A0_ov_00:
LDR R0, =512
BL allocFromGameHeap
MOV R1, R0
LDR R0, =1927
STMFD SP!, {R1}
BL loadFileByExtId_Dest
LDMFD SP!, {R1}
MOV R0, R1
LDR R1, =0x5000200
LDR R2, =512
BL 0x02066F28
B 0x20BD2B8

You don't have to use ASM Hacks for this.

What you have to do is to follow those steps:
_LZ Decompress d_2d_UI_O_1P_course_select_b_d_ncl.bin
_Open that file in Hex mode
_Select All and Copy
_Then open UI_O_1P_course_select_o_ud_ncl.bin in Hex mode
_Select from offset 0x1E00 to 0x1F1F included
_Paste, Save and exit
_LZ Compress d_2d_UI_O_1P_course_select_b_d_ncl.bin

This will modify Palette 15's 9 first rows.
Due to the ASM Hack, UI_O_1P_course_select_o_ud_ncl.bin last 4 palettes are the ones who are actually used as the 4 main palettes while in the Worldmap.


I know this is at best a suboptimal method, I'll give you that, but it was either that or I would still be banging my head trying to figure how to properly load d_2d_UI_O_1P_course_select_b_d_ncl.bin while UI_O_1P_course_select_o_ud_ncl.bin was being tampered with by the ASM.

I see.

Is there anything wrong with how I did it, though?

Short answer: nothing wrong

Long answer: I'm nitpicking here but yeah technically there is a mistake, albeit one that bears 0 consequence, so it will go unnoticed by the casual player but Sub Screen SPR PAL should be the same as Main Screen SPR PAL, but when loading the Worldmap from the Title Screen, Sub Screen SPR PAL is not updated.
It does work as it should when loading from a level exit however.

While I got all of the graphics on the world map to display just fine, it seems that for some reason in-game graphics are messed up.

If anybody could help me find a way to fix this, that would be appreciated.
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Nothing to say, so jadnjkfmnjamnfjkldnajfnjkanfjdksan jsdnvj m.

This didn't happen before started messing with this code hack and I only messed with one file's LZ compression after I applied it, which I made sure to return to normal afterwards. I could still try the nmp method, but 90% of the rom's graphic files would show up in the log.
EDIT: You are more than likely right, though. The graphical glitches still happen after removing the code hack and the files that come with it.
EDIT2: Fixed it.
_________________________
Nothing to say, so jadnjkfmnjamnfjkldnajfnjkanfjdksan jsdnvj m.