Sorry to hear that you’re still having issues. Sorry for the slow response, both Joe and I are attending a conference through this weekend, so Joe will respond with more information later.
It’s curious that it’s happening on a totally new installation in Windows 7 because Joe suspects the problem is related to a SketchUp bug that affects plugins. Do you have a way of installing SketchUp 2015 on your Mac? That’s what I’ve been using for the past couple of years and have never experienced the problem. Also, if you have a error message dump from your Windows 7 installation, that would help as well.
Sorry for the troubles, but thanks for working with us to help solve it. Joe will be back to you later today with more info.