First of all:
Thank you very much Blue, for again coming out from behind - just like you did back then with Shoujo Attack.
I am sure, the full version will be even more fun, but the demo gave me already a nice impression - particulary the two differnt play-modes that you implemented: one-on-one with lemma and three players in the "play Hanafuda"-section are a nice feature. May I assume that in the full version, there will be also a four player-mode? Even though I doubt that with four players, any Yaku will ever happen... ^^;;;
However, I also want to give you a few advices for the full version - particulary regarding the included tutorial, because I was pretty much confused after I read it just once. I think you should point out a few things that are obvious as soon as you have played the game once, but are missing for total beginners (and that's the group that I would suppose the tutorial targets):
1.) The player has only the cards on the hand that he is dealt in the beginning. No additional cards will be drawn to his hand and during every turn, the player plays a card from his hand. Thus, the amount of turns in a game equals the amount of cards that are initially dealt to the players.
2.) The table-cards are replenished from drawn-cards that didn't match any othet table-card and cards that players discard from their hands when it's their move. It is POSSIBLE (and happened several times to me) that there is no table-card at the beginning of a player's move, and thus the player is FORCED to discard a card from his/her hand!
3.) The tutorial mentions that every Yaku is 50 points each, but it is really just a single line that is easily missed among all the other lines of text.
How about adding that strategic info to the included Yaku-sheet?
4.) Instead of describing the drawing from the pile as a bonus-move, how about integrating them in the description: a tactical draw from the hand plus a random draw from the pile that make up a player's turn?
5.) The tutorial mentions the strategical value of the Yakus, but it would also be nice to include the info that they accumulate automatically among the point-related cards that are collected in the player's area and the game announces it as soon as a Yaku is completed.
6.) The tutorial should at least also introduce the area in which all the played cards without points are deposited - because it is a great help for strategical playing - as much as using a strategy is possible because the blind draw makes the game 50% random anyway...
... and regarding the game-engine, I also have two suggestions:
1.) Instead of just making the game say "Yaku" as soon as one is completed, it would be nice if the game would tell which kind of Yaku has been completed - or even better if the cards that make up the Yaku get marked with a colored border in the player's area! Combining both visualisations of Yakus would also make every human player quicker more familiar with the Yakus and their names.
2.) You may want to double-check, if the engine handles the cases of double-Yakus correctly. I didn't manage to make one happen while playing the demo, but it may be a displeasing situation if it occurs during the finalized game and the player looses because the game awards 50 points less than actually achieved. I talk here about the (rare) case if a player gets the last cards that completes two yakus at the same time - as for example possible in the first two Yakus in the left column if the other four cards are alreay in the player's possession and he finally gets also the boxed flowers... Sorry if you already covered that case in your coding, but I saw potential for a BAD flaw in this possible though unlikely situation...
I hope my comments were of any help and I look forward to the full version ... and also to what is triggered by the __________.txt-file!