@Phnord, you were exactly correct.  The current HP on that character sheet is calculated based on a bunch of checkboxes.  It might be nice if it were updated to have a manual HP field that could be used instead.  We decided to create an attribute on each character named manual_HP, and fill it with the current HP, then link the tokens to that.  I wrote a script to handle this for him:  on('ready',function(){
    'use strict';
    var fixNewObj= function(obj) {
        var p = obj.changed._fbpath,
        new_p = p.replace(/([^\/]*\/){4}/, "/");
        obj.fbpath = new_p;
        return obj;
    },
    SetupHitPoints = function(token) {
        var attr = findObjs({type: 'attribute', characterid: token.get('represents'), name: 'manual_HP'})[0],
            srcHP = getAttrByName(token.get('represents'),'hp-current', 'max');
           
        if(!attr) {
            attr=fixNewObj(createObj('attribute', {
                name: 'manual_HP',
                characterid: token.get('represents'),
                current: srcHP,
                max: srcHP
                }));
        } else {
            attr.set({
                current: srcHP,
                max: srcHP
            });
        }
        token.set({
            bar3_link: attr.id
        });
    };
    on('chat:message',function(msg){
        var args;
    	if (msg.type !== "api") {
			return;
		}
        
    	args = msg.content.split(/\s+/);
		switch(args.shift()) {
			case '!setup-hp':
                _.chain(msg.selected)
                    .map(function(o){
                        return getObj('graphic',o._id);
                    })
                    .reject(_.isUndefined)
                    .reject(function(t){
                        return undefined === t.get('represents');
                    })
                    .each(SetupHitPoints)
                    ;
                break;
		}
    });
    log('Setup-HP: ready!')
});
  To use it, you'd just setup the token as normal with it representing a character, then select them and run:  !setup-hp This will cause the script to go through each of the selected tokens, and if they represent a character, find or create an attribute on that character named manual_HP, set it's current and max to the value of "hp-current", then change bar3 of the token to link to it.  At that point, it can be added to the character sheet as a default token.  Calling the command again is a handy way to update the manual_HP field when the character's calculated HP changes.  I'm going to drop a generalized version of this in the github repo, next time I'm working on such.  =D