“Event dragged over” puzzles behaves differently on mobile and pc

Hi, verge team

I found that ‘Event dragged over’ behaves differently on mobile and pc, on pc it work as expected. As ‘Event dragged over’ have three action;
-Start do
-Move do, and
-Drop do
i found that on mobile it skip ‘start do’ action in the procces of touch, ‘start do’ only work when doing quick tap on the screen while two other action skipped, i try to combine with ‘Event click’ to substitute ‘start do’ action, but not working as expected too.
Any solution for this? thanks.

Note: i’m in evaluation process, i already have good ui/ux interaction app on Unity3D, try to migrate to Verge3d-web based, already spend several week to find equivalent functions on Verge3d to make it work similarly , some easy , some other need to be tricky, some working good on pc but not on mobile..