sorry for my poor english.
i also test it on v6.5 and v7.0,  i lay  5$ on greyhound @2 in 2 selections,  on v6.5 it cost 5$ but on v7.0 it cost 10$. 
as i know  if we lay on some selections at one market, for example  there is 3 selection at soccer market with price  2,3,4, we lay 2$ at each price, the total risk is 6$(under price 4), but on v7.0, the total risk is 2+4+6=12$.  it seem that the software calculate the risk at each selection. we need more money to do same thing than before.
i dont know how to upload picture so i hope you can understand what i mean.