Sounds like the boy friend is your main source of information about the boy friend. Hope its all true. My advise is still: trust, but verify and get third-party confirmation of a legal divorce before going further.
Good luck, break a leg, and all that. Hope it all works toward a happy ending where you get the guy, a house, and a successful business.
You situation seem lost floating in a thick fog!
1- In Indonesia you can get religiously married without being recognize by the law and state.
2- The fact that he is married, divorced, separated or single change absolutely nothing at your situation on the business way: HE WILL OWN THE LAND AND HOUSE AND NOT YOU. The fact he is married with someone else or with you change absolutely nothing. You will have any legal protection over your business. In any time he can decide to sold everything, keep the money and run away, and you won't be able to do anything about it.
The only thing that can be different is; if you are LEGALY married, if he die you will inherite the land and house and have 1 year for depart yourself of them.
3- Starting a business... Legaly, without the proper visa and work permit, you won't be able to legaly work or run a business in Indonesia. You can open a PT PMA (international company) it cost around 5 000$ and it's very long to go through the process (count in year, more you paid your agent more it can be fast).
If you intend to do like for the house... here again everything will be at his name, nothing at your's....
4- If you intend to live in Indonesia in the future, without being married the residency visa would be extremely complicated. If you are married, you are under the responsibility of your husband (yah, that mean he can decide to not renew your visa -or- a divorce will null any visa.).
La motivation vient en se motivant ~ Motivation come by self-motivation
In spite of the harsh reality PhilippeD described, Indonesians and foreign nationals do marry occasionally.
Anyway, I understand where Philippe is coming from: I know two (Dutch) women who are married to an Indonesian man and who want to (file for a) divorce. The problem is, they have their lives completely built in this country. There are children, houses and even volunteer and community work. Then it becomes very difficult; they feel they are being held hostage because there is almost no possibility to stay here after divorce. And guess what would happen with the kids if they would leave?
My post was just to emphasize that situations like the ones you describe are the exception, not the rule.
"Science is the philosophy of discovery. Intelligent design is a philosophy of ignorance"
I wonder if there are any stats on the divorce rate with mixed couples? If they would follow current trends they could be 25-50%. It's never nice to consider this, but I think many people could (or even would) get screwed over pretty bad when things go sour. In your home country you have much more of a safety net. (Better understanding of the law, the language and your rights. As well as more friends and family.)
Coming back to the OP; that's a rather unique and exceptional situation of course. Think many people are separated but still officially married when they start new relationships. But not knowing where your 'ex' with your child is after 'giving' her a house and car, and having no idea about divorce possibilities?