FTViewME Trending

I've been asked to add a trend to a PVP HMI. Its only a basic HMI with 5 analogue values that need trending. They are all tank levels scaled 0-100%. I have set up a Data Log Model with my five tags (made sure to start the data log in the start-up page), and have a trend object on a mimic, referencing that data log. Time span (x axis) is set to 10 mins, and range (y axis) is fixed 0-100%.

What i am wanting now is buttons under the trend object to scroll forward or back wards in time (x axis), or "zoom" into the range (y axis). How can i achieve this?

You can use the home/end and left/right keys to move the X axis.

(going from memory because I don't use the trend)
You can use tags for the y min/max. Then change the values of the y min/max tags however you want; ramp up/down buttons, interlocked push buttons, ...?.