Anchor point (pivot) relocation bug in 5.5.1 . and keyboard stop working under 1 grid size

A really anoying bug for me in the editor

when i change anchor point pivot of a mesh to another point symetricaly opposed and start to move the object …the object teleport itself to it s previous anchor point …

so i try ot use keyboard but the mesh jumb by big chunk like if was snaping (all snaping desactivated)

is there a way to make keyboard movement smooth like the mouse ?
is there a way to have a grid less than 1 ?

another bug is when using a grid of less than 1 the keyboard not working anymore …