Lighting needs to be a constant 12-14 hours a day for Hoya archboldiana as it is much more difficult to flower these any other way.  Both H. archboldiana and H. macgillivrayi will go through periods when they stop growing.  When this happens, water at about 50% of your normal amount, or instead of watering once a week, water every two weeks.  When growth starts again, go back to your normal watering schedule.  Temps are pretty flexible – anywhere from 60s F at night to the 80s F during the day and anything in between will be fine.  The plants will benefit from an outdoor holiday during the summer, but be careful not to burn the leaves from too much sun.  That is all of my secrets to flowering this amazing plant other than fertilize with every watering during its active growth phase.