Block compatibility between DraftSight and AutoCAD

Hello, 
I work with DraftSight and I created a Block to automatically show the value of the Z-Axis. I do archaeological survey plans and we need to mark heights for the areas examined. I didnt want to put a simple point on a measured point and create a line where I noted the height (i.e. 300.25m, I did that for years and it took hours). So I created a block that would perform that task automatically. And it works pretty well.

But now I found out that my blocks are not compatible with AutoCAD. And I can't figure out whats wrong.

Does anyone have a clue, what I could try?

Thanky you very much!

Yannic