Does it require cleaning or other maintenance?

Recoh-vert has no planned maintence at all. Its is essentially a smooth bore copper pipe which replaces a smooth bore plastic pipe for a 2.1m length.

Recoh-tray has a smooth domed surface over which the shower water runs and can very easily be cleaned (if required) by removing the trap cover (which is not fixed in any way) and running a special brush around in a circular sweep.

Will it work with dishwashers or washing machines?

No, not really in a domestic situation. However this can de done in commercial situations where many appliances are filling and discharging all day, especially if a buffer tank is employed to balance out the water flows.