It seems the zero profit calculation is wrong. E.g.
BTC 1
Rate 0.00624
Total to buy 160.256
Zero Profit price 0.00726 <<<<<< that should be about 0.00630
What price? Zero profit price depends only from Price.
In order to change currency you need to remove all rules.
I have no rules, this is in the buy or sell side. It never used to be wrong, it is now. And pressing the "generate subsequent order" APPLY button creates the SELL side at 16% when you have %0 Try it.