It seems that one could get started with the
I'm going to start with just one Currency and one Transaction. I created my currency on the Define Currencies page of the BigDoor Economy UI by using the 'Pre-fill suggested currencies' facility. That created 'Bucks', 'Coins' and 'Experience'. I'm not sure about the Currency Type attribute. I'm starting by using the 'Experience' currency with its default Currency Type of Redeemable Hybrid Currency. I imagine the Dollar Exchange Rate setting of '-1.00' indicates that it cannot be converted to USD. Yes, I did RTFM and it lists 4 Currency Types while the UI provides 9 options and the description of exchange rate doesn't address the possibility of negative values. (In the real world, exchange rates are positive real numbers.) The response to my note to the BigDoor Sherpa revealed that the different types don't drive any behavior and the -1.00 was meant to designate currencies that don't 'convert', though conversion seems a bit nebulous just now. I didn't get a good answer as to why zero wouldn't be a clear indication that the currency is not convertible. It seems that there's some single reference currency against which each currency must be pegged. This makes me feel like Belize or Argentina prior to its financial crisis of 2001 though my currency was assigned the same ID as the Serbian Dinar.
I used the Define Transactions page to create a new object titled "Grant experience points" which references the 'Experience' currency with the Default Amount set to '5.00'.
Now to see if I can use the API to initiate the transaction for a user. It's useful to note at this stage that the End User object is created as a side-effect of the first transaction in which a previously unknown user id is specified.