You have to reset the shadow position because of scale? Is that what you're seeing?
The Bug here is, when i move the "Object" with my keybourd arrow keys, the position from the Drop Shadow (on the Text) get changed.
Do you also see that behaviour?
I see the behavior you describe in CorelDRAW 2018.
I see the same behavior and if memory serves years ago there was an explanation on the forum from Corel as to why the shadow position changes when changes to the control object were made. I can't remember what it was but they did explain it.