Alright, here's a few big tips for them *SPOILER ALERT*
For Rama's route :
1. Save Reksa, but be honest and let him go away.
2. Focus on his events and don't see other bachelors events. If his event is not available at the choices, choose to spend time with Granny Sukma/Asih. (Rama hates liars and you need to keep an eye on him in case he tries to do anything rash or showing some suicide-tendecies. And of course, be patient with him.)
For Reksa's route:
1. Save him and Lie to him.
2. Always go and meet Reksa in every chance you could. If his affection reached a certain point when the festival arrives, he will leave and Tamara will chase after him.
That should get you to their good ends ^^ ('Give them the Pink Crystal' option should be available for you)