Help Swapping Pikmin with Non-Article Items

[phostopheles]

Hi, I'm new to hacking and have a question regarding model swapping.  Up until now I've only successfully managed simple things like texture swaps in Brawlbox, so please forgive my ignorance.

I've been using Toad over Olimar as practice, since I feel it has a lot of potential after some beginner-level tweaking in various areas.  Specifically, I've been using this model:

http://forums.kc-mm.com/Gallery/BrawlView.php?Number=17989

Over this PAC, which replaced the pikmin with Toon Link's bombs:

http://forums.kc-mm.com/Gallery/BrawlView.php?Number=17574

Which works great.   A few bones disabled (which I assume is as easy as renaming them, yes?), but no extra glitches, aside from the bombs being their usual Schrodinger selves.  Perfect.

But bombs with Toad are just as unfitting as pikmin, hence my reason for importing over Bomblimar to begin with.  So I tried importing the mushroom model below over the bombs.

http://forums.kc-mm.com/Gallery/BrawlView.php?Number=20004

The bombs only kept the TopN bone, so I deleted everything but that in the mushroom model.  Then I imported the model and textures over the bombs.  Actually, different textures for each "pikmin," but I indexed everything and renamed everything and everything looked great in the AME, so I'm positive that wasn't the issue.  And then I go try it out, and the game freezes when Toad tries to pull mushrooms out of the ground.  No mushrooms appear, by the way.

I've gone through everything and I think the crux of the problem is in the definitions folder.  Bombs have NodeTree (36), DrawOpa (33), and DrawXlu (9); Mushrooms have NodeTree (16) and DrawOpa (33).  There are other differences in the bones-textures folders, but those all seem consistent with each other from what little I know of modelling.  Naturally my knee jerk response would be to get the definitions files into the mushroom model or everything but the definitions files into the bomb model, but because of the limited import options I can only replace files, which results in coming up short in either the definitions or textures folder, depending on which way I replace them.  Which means that I need some way to go in and physically edit the definitions if this is the problem.

So, if tl;dr:

What function do these definitions files perform?
Are they the reason why I can't import an item over a pikmin rather than another character's article?
If so, is there a program that can let me fix this more intuitively than hex?
If not, what is actually the problem and how do I go about fixing this?

Any and all help would be much appreciated.

Peace,

Pho

[phostopheles]

Update:

Just discovered how to add materials, so I tried importing all of the files excepting the definitions files (and when that didn't work, with the definitions files) from the mushroom model to the bomb.  The hangup seems to be in the objects folder.