Greetings,
I just bought me a Yamaha KX8 myself. I did plenty of shopping around for great weighted keys and controllers. I used to have a Keystation Pro 88 (not very good). The keys were okay, but bought it for all the wrong reasons, mainly knobs and buttons.
Anyway, the easy fix to your problem is quite easy. Simply go to your controller assignments and add your maps as you would with any other controller. One thing though, since you can't change control values on the buttons, its hard wired as on-off. If you say, map the mute and solo buttons to Logic, you'll get a momentary press effect. The way around it is, press and hold down the button to map, and de-activate the learn (Command+L).
Sometimes Logic loses track of the mapping values and you'll hear the keys playing again. Solution to that is to open your Controller Assignments again, and got to your maps and select "Yamaha KX Port 2". As it might say "Any" when you first start up Logic on a restart.
Hope this helps. And for the record, The Yamaha KX8 Keys are much better than Akai MPK88. Especially for the money, can't beat the KX8.
Cheers,
LGK
