Hi @Borgelin ,
It took me a while to get Snapping to work as well (long, long time ago…);
Here’s an example of the ‘workflow’: Select a Vertex, G, Z to move it down on the Z-Axis and then, while holding CTRL (Snapping (Magnet) not enabled), hover your Mouse Pointer over another Vertex (that has the correct Z height). So, your Mouse Pointer doesn’t stay with the Vertex you are moving!
I hope this helps.