VLS on approach is actually Vref. The +5kts (Vapp) is for A/thrust lag, ground speed mini is for the wind. Trend arrow is where the speed will be in 10secs if nothing changes. Understand this and the Bus auto flight system works well. It may involve opening an FCOM though, so I see where the confusion may lie.
PS...To a poster above, 1000 feet high at 10nm would be 4000 AGL not 5000. You need to multiply the distance by three not the altitude. This use to be taught before P2F was invented.