I think, Ricardo, that the problem may lie in the programming either of the software or the keyboard. Releases on some midi keyboard are meant for MIDI, meaning the it is strictly an on/off (zero or one) switch. When dealing with controlling Garritan samples, this becomes an entirely different story.
More heavily programmable keyboards and especially weighted keyboards will be able to offer much better input (quite literally) for your software to read and reproduce through Garritan, simply because the attack and release data is THERE, whereas it seems that your K1 simply isn't programmed to transmit that data. Make sense?
When you say that the K1 was limited in representing keystrokes, that, especially, makes me think that this is the problem. I'd suggest trying it with a few different controllers (keeping your software setup as much the same as possible) to see if that really is the case before going out and just getting a new controller. In cases like these, just change one thing at a time and figure what works.
Hope this helps, and happy...well...whatever you were doing! haha
Peace
James
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