OK, you don't need h-e-n for bluetooth mouse to work, it is for USB. Sorry, by no means I want to ignore you, just did not understand from your first post that you have a problem connecting your mouse. extmou does not have any user interface, it is supposed to do exactly what is written on first page, section functionality. You may try to install extkbd, where in UI there is an option to manually connect paired BT HID devices. I suspect that after first connect all subsequent reconnects will be done automatically.