Ripping Romancia: Another Legend, Sprites and Events

[ApraxiumRum]

I got into a slump ripping arcade games sprites, so I changed up a little.
Right now I am trying ripping sprites from Romancia: Another Legend or ロマンシア Another Legend for the PC.
Since the game is hard as super hard objects, I'll not rip from screenshots, I went for the files.

Thanks to some kind person, I got both Nana v1.3 and PS1mple to view and convert .DAT and .grp files to .TIM files.
In addition, he gave me a plug-in for Adobe Photoshop to view TIM files. PS1mple can also convert .TIM files to BMP directly.
But than came the problem:

I got this screenshot from the game by pure luck, before the text above it appeared, BTW.
What I want is the pictures to be extracted in their normal colors (below), unlike (above). And like I said, I don't want to fully play the game to rip its sprites.


I was told that I should edit the image's color palette to resemble how it looks in the game, but how? A combination of the magic wand tool and the paint yielded messy results, as the colors went outside the selection.
I don't seems to find that option in Adobe Photoshop.
Can you help me here? I plan on doing the same for another Falcom Game, Dragon Slayer, New Legend of Heroes for the PC.