Hi,
Without seeing more details on the implementation of your control customization, it's very hard to recommend anything of much value. What comes to mind if using IE is to try adding your production site in trusted sites list, but that can be completely irrelevant here.
Any chance you can email the customized control only, and possibly a simple ListView example so we can study this further. We would be willing to sign an NDA if that would make it easier for you.
In any case, emailing to support, the email will only be viewed by 1 or 2 persons (me and Ori) and we would not distribute your samples in any way.
Please let me know how you want to continue.
Palli