PROBLEM #1
From node "All" possible create hosts with hostgroup from child node. And if open it then from master node (not all) we have host without hostgroup

See images
node1.JPG - host created in "All" node (Master node) and opened from Master node
node2.JPG - same host, but opened from "All" node

"dimir" hostgroup is hostgroup from child node

Same problem in Configuration->Maintenance

PROBLEM #2
Impossible select web scenario and maintenance created in PROBLEM #1 using "Current node" filter

See ZBX-6706 (20) (31)