Normally the 'too many requests' message is a good message to have. It means your EyeTV has already connected to our servers in the background and when you try to connect manually, we're telling you that your system has already connected recently.
If your guide isn't showing, the most common cause of this is that the cached program guide information on the hard drive is corrupt. You can clear this out by going to the Program Guide screen of EyeTV and then from the 'gear' icon at the top of the screen select Clear EPG Database, the cached information will be then be cleared and a fresh set of guide information will be downloaded from the IceTV server.
If that doesn't work, it could be that not all channels have been assigned correctly within EyeTV itself. This can be fixed by following the steps at How do I manually map the channels in EyeTV?