Sorry for the delay, I've been very busy and have only just taken another look at this now. Here is one solution that might work for you.
Assuming you are using the default mutlipage view, create the file:
//summation must equal zero
regex = /\b0\b/;
Now edit the view file, in this case:
line 1087, add in class='validate-summation'
echo "<tr><td></td><td><input id='total".$summation_counter."' name='total' value='".$total."' class='validate-summation' size='5' READONLY></td></tr>";
//around line 550, add the following (anywhere after the formvalidation loads)
$document = JFactory::getDocument();
$document->addScript(JURI::root() . "/components/com_bfsurvey_plus/views/bfsurveyplus/tmpl/custom-validation.js");
Basically this just adds a custom validation (using JQuery), which checks to make sure the total field equals 0, which means that all the points have been distributed. Try it out and let me know how you go.
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