Premiere Titles are generally not supported in AE as separate entities, since they don't exist as such. Only titles added to a PPRo timeline will show up, but may be rendered and merged with the background. So essentially it's not the best of ideas to even create titles in Premiere in such a scenario - you may only end up seeing a ton of placeholder solids or an entirely black canvas. If that is the case, render out the titles to separate TIFFs or PSDs with proper transparency. And yes, the projects should be saved in teh same relative location to avoid missing footage and render errors....
Thanks Mylenium - appreciate the quick and focused reply.
I would like to keep the benefits of the Premiere Pro Titler (to play with the length of time by stretching or squashing the Title block on the timeline; to type in time to stay on screen at end; ease in and out etc . . .). If I do render out a png / tiff / or psd sequence with alpha, and bring that into AFX to play with. Will I still retain the ability to use the Titler features in Premire Pro, or do I essentially have to convert it to 'regular footage' on reimport as opposed to a 'Title?"
You can of course keep the titles in Premiere, but you probably will still need some sort of placeholder while you work in AE, so at least exporting a still frame of the title for reference may be necessary. The rest would be very much an ordinary footage replacment process once you have rendered your AE stuff, just make sure to save the Premiere project as a new file thereafter.