Multichart order calculation is right? Broker doesn't agree

Hi,
I can't understand why on this platform there's this "calculation" which doesn't let you respect the broker's margins. If the broker gives specific margins (for me AMPFutures has 400$ for S&P500 and 500$ for NASDAQ) I SHOULD BE ABLE to trade with just 2k, 3k, 4k or just 1k on this market. I spoke with the broker itself and the customer service said that too, it's easy and every platform respects the broker rules.

In this case Multichart has this calculation which let you trade 1 contract if you have the same amount of money of the market price of the financial instrument (but you have to change the Big Point Value manually, so you won't have the same amount of money if you win or lose the trade) or, if you respect its rules, you have to calculate like this your margin to trade on Paper Trading or Real Trading:

Market Price * number of contracts * BPV

Can you understand this is just crazy, I make an example with Nasdaq:

11.598 * 1 * 20 =231.960€ of margins, are you kidding me?
The broker says I can trade with 500€ on my broker account and Multichart says I should have that amount of money to trade with it? There is a clear problem.

The broker margins should be respected for both Paper Trading and Live Trading account WITHOUT changing any number or data.
I hope I was clear and I'm here to listen to your thoughts