Hi @a.szwyd
Thank you for the screenshots you uploaded in Post 4. Screenshot 2 shows your elevations in column 2 (second from left). Your elevation data shows a range from a low of 0.035m to a high of 0.052m. Believe it or not, these are the elevations you are 'exporting' so if you 'import' the same elevations into a new drawing, you'll get those values. Be aware, those imported values are less than 1 meter!
To fix this you can right-click your Point Group (or All Points if you don't have point groups) in Toolspace=>Select Edit Points=>The Panorama will open=>Highlight your points in the Panorama=>right-click and Copy to clipboard=>Paste the contents of the clipboard to Excel then perform Save As in xlsx format.
Adjust your your new xlsx file to PNEZD or PENZD format (you can rearrange columns and delete unnecessary columns while in Excel). Adjust your Z-values by a factor of 1000 (you can use a formula). Save this adjusted file using csv format. Import your points from the new csv.
Chicagolooper