You can modify orders directly in the FX Pro order grid.

1. You can increase the price of an order by one tick increment by pressing the "+' button. Holding the CTRL key down will modify the order by 5 tick increments, ALT key by 10 tick increments

2. You can decrease the price of an order by one tick increment pressing on the "-" button. Holding the CTRL key down will modify the order by 5 ticks increments, ALT key by 10 tick increments

3. You can cancel an order by pressing on the "X" button

4. You can change the size of an order by clicking in the "Remaining" column, typing in a new quantity value and pressing the "Enter" key

* A tick increment for a brokerage that supports sub pips (ECN model) is equal to 1/10 of a pip also known as a sub pip. Otherwise  a tick increment is one pip value.