I no longer have an X4 to check the spindle set-up for direction control – perhaps someone else can help with this (this thread is old so it may be best to start a new topic asking the question).
In Config. / Ports & Pins / Spindle Setup you can specify a ‘Spin-Up Delay’ – Gcode execution is paused for this period of time to give your spindle time to get up to speed.
Tweakie.