1: Yes, you can upgrade from the lite version to the pro version without losing gallery information as long as you
do not uninstall the lite version, just upgrade to the pro version. Instructions are in the readme file that comes with the pro package.
2: The pro license is
here and it is basically a forever use license. Pro support includes one-year access to the pro forums and one-year download access from the download area. After the first year is over, you can continue to use PhotoPlog without renewing, but if you want continued support and access, then you'd need to renew.