Dude, the very hard mode would be easy, just do this:
Make an exact copy of your game, but make a switch:
Conditional Branch: If Switch (Completed Game) is ON, make it say something like: Welcome to Very Hard mode, this is alot harder. (I dunno lol)
and for the Else case, make it say, please complete the game on normal mode first.
And on the original version of the game, when you complete it, make it turn the switch on (Completed Game)
And on the new version (Very Hard), Just chnage the enemy database or something so the monsters are powerfuller, and you can change prices of items and thing, I dunno.
I've done this before, can't remember if thats exactly how I did it, but it should work