[ubuntu] Xenial OpenVPN Bridged need DHCP and RA

I'm trying to set up my laptop as an bridged OpenVPN (TAP) client for my home network. To register myself to my home network for DNS reasons I need the client to work as an DHCP client. For IPv6 I need router advertisements to work to statelessly set-up IPv6 adresses.

However the NetworkManager applet does not allow me to enable ruing a DHCP client nor does it allow me to allow router advertisements.

Ruing dhclient from commandline works, however due to the coection being managed by networkmanager the settings are overridden immediately.

The same goes for accepting router advertisements: /proc/sys/net/ipv6/conf/tap0/accept_ra is immediately reset to 1 where (according to a guide I read) it should be on 2 for RA to work.

Anyway around this? As the point and click way of Networkmanager is desirable over ruing a command line script.