Can confirm that V360Calc works great on O3DS! (It may take a little longer to load, though) Also, I changed the , button to an e button. (The 2.7182 kind, not the 2e5 kind)

It looks like you are trying to use PUSH for inputs, but it's not what the command is supposed to be used for. Maybe use input instead? (after removing the PUSH statements and the DIM) INPUT "1-7",SEL IF SEL==1 THEN:... And so on.