I have same issue on Windows 7 / 10, 32 / 64 bit.
Start dragging just center of the line looks most successful, but different on PCs.
There is no description for change of moving, as you wrote up/down arrow is now useless but can grab any place on the line.
I did find that I could drag from anywhere, but it still has the aweful effect of only dragging the item of the direction I moved towards instead of the one I clicked/dragged on (move up, item above gets moved; move down, item below gets moved). It is good to see it is not me. I work with FMP15 for my job, but at home I have FMP16Adv. to play with (and trying to make money with), so it is very annoying to me.