Contrary to the previous few responses, I think double L works better than single L because a single L makes the "krill" reference less obvious, which imo is bad because, like I said earlier, the connection between a pokemon and its name should be obvious.
That is in fact the only reason to think two L's should be in the name. But, if I can't change it in the first place, that's too bad. ;)
Though, the reason I believe it should have only one L's, contrary to your statement, because the name will naturally flow with "krill" being the way to say the first syllable. The spelling is one thing, but sounding it out means another. Either way, "krill" is still noticed in pronunciation and writing, just less dominant in writing.
For double L:
Makes a better reference to "krill" in writing.
Full 10 letters in little Pokemon's name.
For single L:.
Shorter name
Better reference to kilowatt.
Reading won't be a pain to see multiple double-letters.
I don't mind anymore. I'm keeping single L. Not because of your claim, Objection, because it's true. But because I like it better. :)
And while I'm on the topic of sounding a Pokemon, it would be nice for a Pokemon's name to flow. Whaiatt doesn't flow unless it's pronounced like the name Wyatt, for example. Pronunciation is important too.
