I'm using VoiceOver:
I've clicked on the message Red: It's your move. I've clicked on the 6 places that say red. I've clicked on all the empty spaces. There appears to be no reaction. I'll try the smallest board, but I don't see how that would help me understand how to move my piece . I have no real concept of how the board is laid out, but I figured I could learn by moving pieces.
Using the long hold to remove colors works fine. Maybe I'll figure out how to make my opponent move 1st, but, again, I don't see how that will help me figure out what piece I can move where. Anyway, I expect I will enjoy this game once I can start learning.