Overlapping and fluctuation ratio
 

Hi all,
I'm currently getting started with engrid and meshing my first cases. I have some trouble with overlapping. It is really hard to mesh the boundary layer without getting an overlapping error, after some iterations and refinement it sometimes meshes the BL. However I get the same error when trying to mesh 3D volume.
Can anyone give me some advise or info about good practices to avoid overlapping?

I have also one more question: after some iterations, I reach a 0% of change ratio, however the fluctuation ratio keeps at 17%. What does this ratio means? It is needed the fluctuation to be near 0%?

Thanks in advance,
Regards