where to place M4L instruments so they appear in MAX ?

Kasper's icon

Hi
I own LIVE but never use it - however I try to use some of M4L plug-ins in Max, and some appear (on the left side of the patcher, in the plugs menu) and some do not. For instance additive heaven is there but when I recently installed Bertha 2 (made by max for cats) It shows in Live but not in max... is there a specific folder to "show" to max so it works?
kasper