casio ctk-411

got a casio ctk 411 keyboard
it has midi in/out and is all connected up to pc

the ports are working on the pc also, but -

how do i get a midi programme to playback thru this keyboard?

what music apps/sequencers can you suggest that will work with this keyboard in and out editing and playing back midi files and also edit wave/mp3 files

Im not sure if this is what you meant but heres a freeware editing program

http://www.thefreesite.com/Free_Sounds/Sounds_freeware/