Player Object - Set Key action

I notice that when you select the Player Object's "Set Key" action, it prompts you to press a key right then and there in the Event Editor. Is there any way that I can input a string or number instead?

Currently, it seems that I cannot reassign the player's keys dynamically without the Control X object, which has no Flash support. If I wanted to make a Flash-compatible game with customizable controls, would I have to manually make events for every key on the keyboard?

You can do this with the Control X extension, but I don't know of anything else to do it with. Don't know if there is anything that supports the flash exporter