There is no "common" overlay page. In fact, that feature was added to support 1 thing. The TSX9500 in wall panel that did not have the extra set of hard buttons or wheel.
If you don't put a lot of ProntoScript into activities, you could simply 'Jump' to a Page in a different activity that contained your overlays. You could then put a timer (CF.activity().scheduleActions or Page Script repeat) to allow you to jump to a different place or back to the page you came from.
If you create widgets on your own for overlay pages, then that is what you get, they don't slide in, etc.. unless you move the widgets around onscreen via script.
I spoke to the ProntoTeam when they introduced this feature. My biggest complaint was having a single page that was the Overlay page. As such, it is like the Home page in that you can never copy/paste it nor can you rename/delete it. The only way to capture what is on the page is to open the page and do Ctrl-A to select all.
One other note (please excuse my ramblings here). PEP3 was never fully shaken out and can crash at times. I am a solid user of PEP2 and will continue to use it. I installed PEP3 at one time but have since removed it.
If you'd like to discuss further don't hesitate to shoot me an email.
