Extremely well done. I've finally found some time to try and solve the maths puzzle and I think I got it. I'm sure it took a lot of work to design all of these fun little riddles and to find these different ways of teaching the player new words. Something like this would be really cool for learning an actual langauge. Also the nice animations and bigger character sprites make the dialoge really enjoyable.
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so on to the numbers...
I think:
1 = kwuz
2 = stomb
3 = wito
4 = lmai
5 = tuipa