For the old WP install to understand the new directory structure, you will need to convert all instances of public_html/WP/ to public_html/philuxphoto.ca/WP/ in your database. You might want to just open the SQL file and do a find and replace. Make sure you also do a find and replace to replace the old URL to the new one.
Plugins will still work, although I did encounter issues before where data from my widgets were not preserved. Reason for this is that the data is serialized, there's a good explanation of it here.
If you're planning to port another site over, you might want to use this plugin for getting the SQL dump - makes it easy for you and you won't lose any data too.