The multi-instance support is mostly finished. What could still be improved is the detection of devices. But that is another story, as it would require mapping each device to the correct multi instance device templates. I.e. the EZMotion sensor should be added as one motion detector and two multilevel sensors, but as the device reports itself as a multilevel sensor with three instances, it is currently added as three multilevel sensors.
But they are not added as child devices, but as three devices on the same level. This is because one device can contain sensors that are of different types, like the EZMotion, it has two climate sensors, that needs to be added below the climate interface, and one motion sensor, which needs to be added below the security interface.
I haven't figured out the proper way to do it, but it should be along the lines of the already existing device template system in LMCE. I'm not actively working on this, so anyone should feel free to take it on