I am running your webpart on a site that has https - the web part is working, but I am prompted with the IE dialog "Do you want to display nonsecure items?" every time. I have narrowed it down and it is your web part that is causing the prompt. I purchased source code and I assumed I would also be getting the flash source code, but that was not included...
Anyway - can you test this using https and correct the issue? When I view source I can see that the flash object is correct identifying the location of the xml and the swf with https. I can only guess that the flash object itself is not calling the xml file properly - i.e. with https.
Thanks,
Jason