Making ETH transfers in Azure Blockchain Workbench

Has anybody done a payment on ABC Workbench?

I mean, <address>.transfer(amount)

When trying a transfer, I get this error message:

This is taking longer than expected.

Questions:

• How do I find the address of a user account so I can check their ETH balance with Metamask?
• What is the Ethereum RPC endpoint that I can use in Metamask to access my Ethereum ledger?
• How do I transfer ETH from a user to another one?
  

The code I'm using is:

address public Gambler;
address public Bookmaker;

function PlaceBet(string score, uint256 amount) public payable
    {
        if (amount == 0)
        {
            revert();
        }

        if (msg.sender.balance < amount)
        {
            revert();
        }

        if (msg.sender == Bookmaker)
        {
            revert();
        }

        BetScore = score;
        BetAmount = amount;
        State = StateType.BetPlaced;

        Gambler = msg.sender;

        // THESE BOTH FAIL
        // Transfer amount to the Smart Contract account
        address(this).transfer(amount);

       // Transfer amount to the Bookmaker
       Bookmaker.transfer(amount);
       
        ContractUpdated("PlaceBet");
    }