the forum is the best mechanism for that.
Just post something in the forum. That's it's purpose. To get that notification out to forum members.
This is their integration forum. I've posted a thread requesting the NodeBB-OpenCaart interface, the thread has not as of yet been approved by mods. But, we could easily do the same, yes? We really do need a cart/store and integration opens up an entire constellation of functionalities.