Stratigos,
this is a user forum. I suggest you ask Cakewalk support.
I can't really understand what your problem is, so I can't offer any help. I think you are wanting to control something with velocity, but I'm not sure what. Volume? The volume might be limited on how low it can go because of another controller (amp envelope or SFZ). Try loading a different sound into a single element and see if that works how you want it. If it works like you expect, it is probably in the SFZ file definition. If you have the same problem, it is probably in the amp settings.
Sorry I can't help more.
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