Allow content type - Group manager

Hi!
I am running Organic Group 5.x-5.0 and the group manager can not change the content type in their groups.
If 'site admin' has defined a content type as 'allowed' (but not 'required'), then the group manager can not activate that content type in his group.

Like this:
Group manager goes to: www.example.com/node/132/ogct
Checks the box for 'Conten type X'
Presses 'save assignment'
And now the box is back to unchecked...... and the content type is not available to the group members.

The only way I can activate the a content type is by choosing 'required' as a 'site admin' for a specific content type and a specific group.

My OG modules:
Organic groups 5.x-5.0
OG Content Type Admin 5.x-1.4
OG forum 5.x-2.x-dev

Any ideas?

Thanks!
Seth