launchpad madness

I am totally going bonkers...... how is it possible such a simple task does not work. I want to use a launchpad (page, custom mode whatever you call it) as a 8x8 matrix. When pressed , a note on or a cc should be send, the LED stays on. Pressed again, note off or cc is send LED goes off.
But I just can't get it to work.

but while researching I found other cool stuff relating to launchpad and LED. Did you know that there are launchpad artists out there? musically not my cup of tea, but I realised that is really cool stuff you can do with the launchpad. as soon as I found a solution for my problem I'll dig into launchpad lightshows deeper at some point