While converting from usd to btc I found this also.
I had to set BOUGHT_PRICE on each pair.. (no problem)
The BOUGHT_PRICE was honored with the bot.
But when the pair sold it counted the whole bag as a profit and added it to ~/json/pileupfunds.json
So if you were to have bought btc-eth in usd in a vlaue equal to .006 btc and it sells for .0065 btc then .0065 would be added to the ~/json/pileupfunds.json value.
I wonder if that is something they can look into fixing! And I hope that all makes sense!