Suggestion on help files for this template: it might make sense to add some developer notes on modifying the template, because when you do something like (say) add a checkbox, you have to take special steps in Bootstrap, otherwise it won't show up.

Checkbox not showing on bootstrap template?
a) put it in a special div
<div class="custom-control custom-checkbox">
b) input first, then label.
echo zen_draw_checkbox_field($bucketfee_id,'',false, 'id="'.$bucketfee_id .'" class="custom-control-input"');
echo '<label class="custom-control-label" for="' . $bucketfee_id . '">' . BUCKETFEE_QUESTION . '</label>';
c) On label, use class="custom-control-label"

Radio buttons? Similar fix:
a) one div per radio button
<div class="custom-control custom-radio"
b) input first then label as above
c) On label, use class="custom-control-label"