It's not really clear what you're talking about, so I'll try to sum it up:
Draglet is a provider of white-label bitcoin exchanges.
1. you agreed to pay $53K to draglet for 16 months of service
2. you offered to pay $4K per month of service instead
3. did draglet actually agree to that offer?
4. launch of your exchange was scheduled for 30 days before launch? I don't understand.
5. you did a prepayment of ~$1100
6. draglet delivered an install script?
7. you now want to pay the first $4K after launch of your exchange?
8. draglet asks for payment of $xxx right now?
As far as I can tell, this looks more like a misunderstanding of terms on either your side or draglet's, or both.
I happen to know the people behind draglet and I'd be surprised if they tried to scam you for a few thousand $.
They're trying to establish themselves as a service provider with an ongoing income stream so they have almost nothing to gain from one-off scams for a few bucks.
1. Yes we agreed to pay $64k to draglet for 16 month, not $53k
2. Yes
3. Yes they agreed
4. For example, im my trading platform was a few options such as Margin trading, Swap trading, Real-time chart and etc.
We told draglet for complete our project then we will pay your first payment($4k) 30 days after complete of project. they agreed, but now not!
5. Yes, BitPay invoice:
https://bitpay.com/bill?id=HnVnxo6bnCrHAtNPgf7SM4&resource=bills6. Yes, but we didn't access to server root, we changed our DNS.
7. NO, we don't trust them because they broken our condition. now we want refund ~$1100
8. Yes, $4k
They want that we pay item by item, (for example for Swap trading, we must pay $15k) but question, why we sent offered monthly payment to 16 month?
Because we have business plan and we don't want pay item by item.
They broke their promise!