Hi!
I have updated my mikrotik RB450 to firmware version 6.5 from 6.2. Removed default config to start from clear. I need OVPN Client, so I took my certificate, key and CA to import. Nothing happened when I pressed the "import" button! Neither from winbox, nor from terminal. And CPU gets 100% until I reboot the device.

By the way "import" works correctly in version 6.2 with the same certificate. So I the first time used option "/system package downgrade"

Wait for 6.6. It should be released shortly. And then post your feedback again, I am courious how to work with certificates in 6.6 because there were major changes to it.