Freeform question issue: items not appearing in center

Y'all,

I made a freeform question in which users get to drag n drop upcoming items to the right box. 

In the drag & drop options (design tab) I've set the drag item options to

[X] reveal drag items one at a time

So the items come up one by one. 

The items contain also an animation 'grow' 

Problem: The items don't come up from their original position. When replaying, they do but initially they don't...

Anyone familiair with such an issue?