How to Apply Vertical / Z Offset to Element?

Hello,

I am operating OpenRoads Designer Connect Edition 2020 Release 3.  I have a DGN file that is just a bunch of lines.  These lines have elevations associated with them and are considered to be in an older vertical datum which I would like to update to a more current vertical datum, which happens to be 3.845' higher.  I determined that ORD does not specify vertical datum - please tell me if I am incorrect in that. 

Ultimately, I need to apply an offset to all of the elements in the drawing, so that the file can be considered to be in the updated vertical datum.  I figured there has to be a way to apply a z-value to the whole drawing / set of elements, however, I cannot seem to find a way.  Is there a way I can select all of the lines / elements and enter a vertical offset or z value to the highlighted selection and apply it so I can save it and be on my way?  

*Top view / Birds eye view

* Right view - I would like to apply a vertical offset and essentially just move everything seen in the screen, up 3.845', to meet my new vertical datum requirement.  I want to leave all other XY coordinates and location the same, just move all elements up a certain distance.

Can anyone help on this?

Thank you in advance!

Neil