This is an issue you will find with a number of the templates, NTSC, PAL, HD etc. Find the template you want, open it in Motion, change the project settings to match your requirements, resize all of the motion elements to fit the new project settings and framing, most are vector objects or at the least the slight scaling will typically not be an issue. Once complete save the project as a new template within a template folder relevant to either the project or template. this folder will then appear in your masters area of FCP and continue to be available to you for all future projects.
But enough from me, there is a tutorial on the apple site that covers this
http://www.apple.com/finalcutstudio/tutorials/
and select the creating titles and templates button below motion.
or direct link
http://www.apple.com/finalcutstudio/tutorials/#tab=fcstudio&tutorial=mov-mottitl es
Tony