Yes, trim basically electronically adds a small amount of control input in the direction of the press, the idea being if you are having to constantly hold forward stick to keep it in one place, click the forward trim a couple of times, ease back on the stick and see what happens. Rinse and repeat. The goal is to add just enough trim so that when the stick is centred it doesn't want to move forward any more (apart from under the influence of its own propwash, any wind, the cat... manual mode, right!?). If you need more that 4 or 5 clicks then try recalibrating on a tilt as I mentioned to get it nearly there, then use the trim for getting it right there.