Your base currency is HKD, so exchange rates must always start from HKD. Enter rates as 1 HKD = X USD. If you enter 1 USD = 7.8 HKD, the system treats USD as the base and breaks P&L and balance sheet reports. This is expected behavior, not a bug.
Thanks. I figured as much but wanted confirmation. BUt one would think if it was the other way around, the software would have adjusted accordingly. Logically, since the software can have multiple currencies, it would have been able to check what the acocunt currency is and convert to the base currency whether it is 1 HKD = ? USD or 1 USD = ? HKD. But anyway, that is for the developers to sort out.