Anything that includes this <script type="text/worker"> is describing how to edit a character sheet - it's designed for the script block of a character sheet, not the API and won't work there. For what you need: if the sheet doesn't include a total attribute, you can't add it to a token bar the way you want to. You can create a new attribute, using a script like ScriptCards or setAttrs (or just manually add it to the Attributes list on the Attributes and Abilities tab - - but the script wroute is needed if you want to autocalculate the values, and you'd probably need to rerun it each time you want the attribute changed), and then put that attribute in the token bar. You'd need to create the attribute for every character. Vince's suggestion of making a custom sheet based on the existing Kids on Bikes sheet is the best solution (and adding a sheet worker to calculate the attribute), but you won't get updates if the sheet is still being updated.