As for this current version (and what I have found so far):
Discards by default are 0.
Xmult doesn't show up in the red scoring, only in the final score [which made me think first that it was bugged and didn't work].
The fact that the key "i" shows the Run Info isn't displayed anywhere.
Secret hands are not implemented and are bugged [As of right now I've only been able to try 5oaK, and it defaults to High Card].
High Card does not score chips.
Viewing post in Balatro for the Commodore 64 / C64 (work in progress) comments
In normal balatro, Jokers like Jolly Joker (+8 mult if hand contains a pair). in this version, it only activates if hand is a pair, not if it contains a pair.
When you sort by Suit, the next round it will sort by Rank while the button says Suit; you need to toggle it twice to sort by Suit.
Also, you start with $0 instead of $4, which makes it harder.