My RB450G + ROS v3.30 work very good. When I installing total packages v4.3 do not work all ethernet ports. If I disabled ipv6-4.3.npk, all ethernet ports begin to work, bat if I change names or MAK-ADDRESes of ethernet ports and reboot router, first port not storred changes.
The problems will be fixed in the next RouterOS version (4.4).
I have downloaded and installed the 4.4 version of RouterOS. The problem is fixed indeed. Thank you.