As LED fittings are getting very efficient these days the wattage of each fixture is not very high (3w to 15w for a downlight)
But when you add a new single fixture in to program on LED DALI load type you can only assume it is for one DALI driver for one fitting.
Drivers are getting larger in wattage 30w to 50w for series wiring, so you can have several fittings on one driver.
Would it be possible to allow to have several fittings (fixture Qty) on one driver for a particular Zone ?
This would allow for correct loading to be calculated.