1) Usually at or before the MDA or DH.
2a) Yes. Use the "minute to live" rule - vertical speed is no more than your altitude above the ground.
2b) On this approach (VOR DME Rwy 02) I would configure to final landing configuration outbound from the VOR. Keep autopilot connected until inbound to D7.0 fix. Disconnect autopilot and use Flight Director for reference. Have PM set MCP altitude to 6700 and vertical speed at -2000FPM. Passing D5.0 fix, set altitude to 5700. Approaching 5700', look for runway. If in sight, continue to 5000', then decrease to -1500FPM until on the PAPI; if not, go around.