Mail Hosting not working, Transparent logo background appears as black

Mail Hosting not working, Transparent logo background appears as black

Hi,

Mail Hosting issue
I've added my domain and enabled mail hosting at zoho.

I've changed the MX records in the DNS at my Domain to mx.zohomail.com (Pri 10) and mx2.zohomail.com (Pri 20) but my emails are still going to my original mail server where my websites are being hosted.

Do I need to do anything else?  How long does it take for the DNS changes to propogate?

Logo background appears black
I've uploaded several different versions of my logo (1 is attached) and the transparent background always appears as black. OK in IE and FF.  I'm using FF7.0.1 and Win 7 Prof.

Any help gratefully receivedKeith