To quote from the
README:
... Daemons which support local work creation through the getmemorypool call will have two extra fields "Pay To" and "Tag". The former will override the default payout address on block solves; if you leave it empty, ecoinpool will create an account called "ecoinpool" via RPC call and use this one for payout ...
I'm not lying in that
README, it's true!

Congratz on setting it up, so it was possible to bypass the frontend error messages involved in first worker creation. Good to know.
p2k