[grumpyunk]

As far as I know, titles from other states are respected by the receiving state. To do otherwise would be to act in restraint of trade between states, and that's not allowed.
California has some rules about non-CA emissions vehicles being imported from other states, they sort of allow it, but restrict the resale of the vehicle. IOW, if you bring in a non-conforming vehicle, it may not be resold within the state. They do recognize the other state issued title, but place a restriction on the CA title they issue, indicating it cannot be resold within CA.
Here in GA, vehicles past a certain age are not issued a title always. You can ask for and pay for one, but it is not required.
You should have no problem re-titling if you move. Once it has a title, it is generally not looked at too closely for FMVSS and EPA compliance. CA may be the exception, along with NY (and several other states) which follows CA emissions practices.
I have had dealings with the C.A.R.B - CA Air Resources Board - and they are very particular about how things are done. They will certify after-market catalytic converters to be installed in place of failed units, but the makers have to pay a big chunk to get them certified, so generally replacements are limited to OEM. A set of headers can't be installed and pass inspection without a CARB certification. Cars are junked or exported where the cost of replacement converters makes it too costly. Ugh.
tom
tom