Hi,
So much information. Apologies if answered elsewhere.
I have been running Workshop 6 with 4 currency pairs. I had been running on a $10,000 demo account.

To try and make this more realistic (for me) I set up the demo account (FXCM) with $500. The account has been running since 5th November. The first Trade was midday on 7th November (EURUSD) . The Trade used 0.21 lots which seems excessive on $500 account. [I now see Capital = 10000;in the code - does this govern Lot size?]

The trade stands at +$231 (great but risky). Just opened 2nd Trade on USDJPY with 0.16 lots.

How should I control the lot-size?

Better close those trades. The workshop 6 script assumed that you have 10,000 on your account, not 500.

Set the Capital value to the amount that you have on the account.

Many thanks. Got it