No.2446
Try looking up Wine for Mac. It is a system that allows for the execution of Windows programs on other systems. I am not sure of its compatibility with .flow.
No.2514
Crossover for Mac works pretty well.
Just go into system preferences and change your computers language to Japanese, download one of the PC versions and rpgmaker2000 (or whatever other things you need), create a new bottle in Crossover, and run it.