The winch uses a 415 Volt 50 Hz AC motor, so both the up/down and run/stop controls actually operate +24V relays, whose contacts switch the 415Vac to the winch. The relays also provide electrical isolation between the LCU and the lift equipment. In your design you must include suitable interface circuitry to drive the coils of the two 24V relays.
(Note that the 24V power supply and the connections from the relay contacts to the winch are not part of this design problem.)
The lift position sensor provides a 0 - 5Volt analog signal indicating the position of the lift over the range 0.0 to 6.4m. An 8bit ATD converter converting this signal to a single byte value would give $00 to $FF representing positions 0.0m to 6.375m in steps of 0.025m.
Unless otherwise required (Eg. the relays) all signals require no special buffering to/from the controller. All signals in-to/out-of the controller must be interfaced through a connector, and must provide a 0 Volt (GND) supply reference.