Electrophysiology Spike Sorters

Hi,
I'm trying to use Waveclus/Kilosort spike sorter but it appears to be gray (inactivated) in my window. Not sure what I'm missing there ? Please advise.
(My data is filtered and preprocessed in MATLAB and is in .mat format and I see that the data is imported/loaded correctly as it looks right (same as MATLAB o/p) after I open it in brainstorm).

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