Returning to ldraw, mlcad parts tree help requested

[Patrick Campion]

Hi all, my name's Pat. I've just replaced my 13+ year old home computer with a new one and I'm just installing ldraw again. Question I have relates to the parts tree hierarchy in mlcad. When I installed this all those years ago, there was a some kind of parts tree tweak available that I had installed that separated out, for example, all of the different brick types (decorated, modified, etc.) such that when clicking on the basic brick category, exactly and only that would appear in the parts preview pane, basic bricks only. Would dearly love to be able to set this up this way again.
I have no recollection on how I managed to implement this reorganization back then. Any direction on how to do so again would be appreciated.

Thanks