Hi,
I have been using Abatron's system steadily since 1986.
Now, I'm no expert, but I have had the best success coloring the itself rather than trying to stain it to match after curing. I used powdered wood dye for this purpose, as it does not thin the product or impede the curing.
Casey

So you mix the Part A and Part B together and then add the powdered wood dye with no additional solvent? Does the color stay the same before and after curing? What brand or brands have you used?

I always treat it as a little decorative project.

Make sure it is lighter than needed and use permanent markers, paint, etc. then put a clear finish over the detailing to protect it longer term.

It will NOT be the same color as any wood finish, but require careful work to get it even similar.

'Stainable' means it takes stain.

It does not mean it takes stain like wood (or any pother material) and matches without a lot of work.

You must experiment with test batches to get the color match before you do the actual repair. Powdered aniline dye intended to be dissolved in alcohol is what I have used.
Casey

"Powdered aniline dye intended to be dissolved in alcohol is what I have used. "

And go lighter so you can go back and add the darker grain detailing afterwards.