Yeah you are doing great. To be honest this whole thing is tough no matter where you live but being in a country that isn't your home land!!!! I really can't imagine the stress you must be under.
I'm no lawyer. But I can't imagine many countries allowing a parent to vary the agreed child support ie reduce it in anyway without going to court. Certainly in the UK he would be able to reduce the payments if he has the child for longer than a few days per year. I'm not exactly sure on the figures but as long as he has the child more than 52 days a year he can reduce the payment by 1/7th etc in muliples of 7. Yeah yeah it's unfair beacuse housing, clothes, treats, school trips, and holidays still have to be paid for but that's how it is here.
Again he shouldn't be able to force you out of your house assuming he has adequate housing. Your h has adequate housing doesn't he? Surely the child takes priority.
Also he'd have no chance of getting 50% of anything. You have a reduced income due to your comitment to your child and so are entitled to some compensation for that. IMHO.
You do need to get further legal advice by the sounds of it. And yes that SA needs to be in English. As for your mothers estate I think you need to make enquiries about that too. I think here he would be entitled to some of that (sorry as I say I'm no lawyer so don't be scared by that....I'm probably wrong).
I know that your an avid reader but there are some good websites that may help you.
Lol @ him wanting to stay the night. You know his games Liv. As much as I like the sound of your sister I think it would be better if you keep her away from him.
Anyway, I just wanted to offer some support. I'm thinking of you.
