With the new 8.0 release, MarkupList items can no longer observe "focusPercent" and therefore can't handle focus properly. I tried with 7.7 and it is working there.
Is there another workaround?
SOLUTION: change the type="integer" to type="float"
<field id="focusPercent" type="integer" onChange="onFocusChanged"/>
<field id="focusPercent" type="float" onChange="onFocusChanged"/>
