the vast majority of 3ds Max's native objects that display their properties in Main Command Panel usually have Enabled or On checkbox at the very top of the first rollout. This actually does not apply to most of the native objects, but also to most of the third party plugins honoring this standard.
Forestpack on the other hand, has an arbitrary and significantly less intuitive place for this control. It's in the very last rollout, called display, which (wrongly) implies the controls contained are actually related only to viewport representation of the Forest, not affecting the way it is displayed rendertime. Moreover, this control is actually inverted, called "disable object", and buried inconspicuously in the middle of the rollout.
It would be appropriate to rename this control to "Enabled" or "On" and move it as very first thing in the general rollout, to keep ForestPack in line with 3ds Max standard.
I only found about ability to disable Forest objects when I discovered forest lister, and it took me quite a while to figure out where that setting is in the command panel display of the forest object.
Also, I would recommend putting "About" rollout as the very last rollout, as it contains the set of controls least relevant for the actual work. It makes no sense having it as first rollout.