1-3: Good to know.
4: I'll probably go with ALGUNO/A for dice, then. For coins, do you think people would understand 'M' as 'moneda'? e.g., 'ALGUNO_M'. Similarly, would e.g. 'ALGUNA_D' work for 'any domino', as in, a domino that could be any number on both sides? They'd only be used in situations where other coin-flips/dominoes are being used, so people would already know what objects are being used.
I'll also be putting out a test document (for sight-readers and TTS users when the icons are done, so there'll be a chance for revisions later.