Well, the DKC3 GBA board had one, why not DKC2?
Any changes you noticed between the SNES and GBA versions you can post here.
-Krook seems to have a greater delay before attacking, he also doesn't turn around if Diddy/Dixie approches from behind.
-You can kill Kruncha by jumping on him with both Kongs teamed up, whilst in the SNES version he'll just become angry.
-In Animal Antics, the mid-way barrel is moved to the start of the Squarks' section, instead of Squitter's section. Red Zingers that moved in a circle near the end of Squarks' section have been replaced by Yellow Zingers. Rattly's barrel has been moved slightly, and a blue balloon can be picked up above the Rattly transform barrel. In Rattly's section, there's an extra part added. At the very start of this section instead of heading right towards the Klampon, heading left will take you to some extra Zingers, spikes, some banana coins and a collectible photo.
-The timed barrels in Fiery Furnace seem to count down quicker and/or move slower, I don't know if that's just me, but they seem to have less distance in comparison to the SNES version. Also, I find that the DK coin is harder to get in the GBA version as there's less of a gap to move in between the Zingers, probably because of the sprite size differing from the SNES and the fact that they move slower and with less distance.
That's all I can come up with for now.