Dear Ian,
As far as performing a marriage ceremony, Lama Yeshe used to perform a ceremony such as Tara Puja. As a monk you can't say you are asking them to get married. You just perform a puja for their wellbeing, to lead a meaningful life, and especially that their wishes are fulfilled – to be able to cause others peace and happiness and to serve others. Tibetan people do pujas for peace. That is also possible.

Even if you become enlightened, normally you don't announce to others "I am an enlightened being." The most important thing is to be humble and to live a pure life, to practice Dharma well. Then one can benefit others. Otherwise, you can't benefit others, even if you announce that you are a reincarnated being. Even if people follow you, it will only be for very short time; it will not be long lasting. Then, you can't be of much benefit.

About the house for sick children, I will check on that, but first please tell me who told you about your past life, if it is a pure source. I would like to know who told you.

With love and prayers,

Lama Zopa