Hi, I think it is a real pity that this issue is dormant at the moment. It really makes lyx almost impossible to use for writing long text and that is the major use case after all. Since the number of people who will be affected by this is bound to rise a fix would really be appreciated.
I do not know whether this helps a potential developer taking up the issue but using lyx under Windows on a MacBook Pro Retina works without a Problem. If someone would decide to take this up I could offer testing as the hardware is probably not that common. Regards, Julian