Connectors not lining up

I am really frustrated at how the connector lines in Omnigraffle 6.0.5 are not lining up and are never 90 degrees.
I am using a colleagues document that was created in PRO and they just bring their lines to the box magnets and everything lines up perfectly - 90 degree angles.
When I do the same, the lines are never straight and I basically need to zoom into 800%+ in order to tap over. Holding the shift key (as a basic mac function) makes no difference.

Is this ‘ease of use’ and basic functionality only available in PRO?

Im wasting so much time - help!