Hi,

Zorro by default requests Ask prices unless you use BrokerCommand(SET_PRICETYPE=2) - which has been introduced in v1.72+.
Quote:
The IB Bridge now downloads prices in 1500-tick packets, which increased the download speed by up to 30%.
The IB Bridge now supports the SET_PRICETYPE command with parameters 1 (quotes) and 2 (trades).


Except the Low at 20:59, your prices (from IB TWS?) are lower then Zorro's - possibly reflective of the Ask-Trade difference.