Big Sur cannot install Big Fish Game Manager

Since 1997 on all my macs and all software updates I have played Big Fish Games (have at least 100 in my account) Recently bought a new iMac version 11.2.1 running Big Sur. I cannot install Big Fish Game Manager. Yes, I have contacted Big Fish but with no reply except free games which is ironic. I have visited every FAQ and discussion format with no solution. If Apple is wanting us to use only Apple games, then at least let the client know so monthly billings at Big Fish can stop and they know they have lost all their games. I want honesty.