You're in a tough position.

Look at Win32::GUITest first, which implements some VB/SendKeys commands better than VB.

You might also be interested in SAMIE. I've corresponded with SAMIE's maintainer about the small amount of JS support SAMIE offers, he might have made more progress since then.

Also, search CPAN for JavaScript modules, something there might help. (But I haven't found it yet.) Driving JS interfaces with automation seems to be non-trivial.

Good luck, hope that helps, I'm very interested in what you come up with!