Hi, I can help you with your IE9 issues, but it is going to be difficult without seeing the site as it is on your local development stack.
I just tested the plugins in IE9 and it is working.
So it sounds like a Javascript conflict is the problem.
The first thing I would recommend doing is using the Developer Tools with IE and finding out what is in the console for errors. You can post those errors here if you like and I can try to help resolve them.
Also, if you can move the site to a development url and we can see the site I can provide much more support then this.
Let me know what you find out in the Developer Console and we can go from there.
Thanks