Hacking How can I recompress ARM9 for Metroid Prime: Hunters?

[atrueboss]

I am currently working on a balance mod for this game (making all the weapons and hunters balanced by changing values in ARM9).

The file needs to be decompressed in order to do anything practical.
Finding the values and editing was done with brute force and is no issue now.

The problem for me is that I need to recompress the ARM9 before I insert it back into the MPH rom. If I put it back in decompressed, the game works but suffers memory problems when playing online due to the ARM9 file being larger than the original because it's decompressed, leading to crashes.

Does anyone have a solution to this problem? I have tried using BLZ compressor by CUE but it always gives me this error when I try to boot the rom in NO$GBA.

"Undefined opcode - with no debug vector defined."

 

[FAST6191]

Are you sure it was compressed to begin with?

A recall an older thread wherein I think it was that game which Crystaltile2 false positived as compressed and caused some woes before it was figured out.

 

[atrueboss]

Yeah I'm pretty sure it is.

It can be extracted from the rom either compressed or decompressed using EveryFileExplorer and they give me different files. One 500kb and the other 888kb.