Beginner Question about Changing a Kit

[akpop]

Hi, I'm new to kit building an ran into this problem with RMV 5.0.3:
I built my own kit from wav files and saved it. All went fine.
But now I want to add a crash to my kit. I select an empty pad and can load the sample files but the pad just won't trigger!?
Am I missing something or is it impossible to alter kits by adding samples into formerly empty pads?

[TonyBy]

Hi.
There's probably another pad somewhere set to the same note number ??