Personally, I don't use physX. I'm planning to try it out myself.
As for your image your trying to add to your sig, you have to load it to a server.
1. Go to this site: http://imageshack.us/
2. Click browse and find the image you want in your sig. Select it and click Open.
3. Under the yahoo ad there is a button that says "host it!". Click it.
4. Then a page will come up with a lot of information. Scroll down until you see the text "Direct Link" and copy the URL in the box next to it.
Then, edit your sig so it follows this:
[img]Paste the ImageShack direct link URL here[/img]
Just replace everything between [ img] and [/img ] with the Image shack URL.
Hope that helps.
dbPrint ( "Sig" );