You can reset the value on any areas you modified. Go back into the style properties categorystrips and you'll notice a checkbox in the top right. Make sure that is ticked and then update style and this will revert the changes you made and revert back to the default.
You're welcome but i don't think I helped much since you never managed to alter your categorystrip.
Kelvin if you still wanted to change your categorystrips and you want me to take a look at it (will have to be tomorrow) I'd need access to style properties. Feel free to send a pc if you want me to take a look tomorrow my time.