As for cinders here's an example of why it's going wrong:
[19:44:28.652] Acid Rain Acid Rain Plakkie 160875
[19:44:30.667] Plakkie Renew Plakkie +13495
[19:44:30.909] Flaming Head Cinders Plakkie 136500
[19:44:31.515] Elzabet Healing Stream Totem Plakkie +*70664*
[19:44:31.866] Flaming Head Cinders Plakkie 74587
[19:44:32.740] Elzabet Riptide Plakkie +23805
[19:44:32.944] Flaming Head Cinders Plakkie 74587
[19:44:32.944] Plakkie Renew Plakkie +13494
[19:44:33.161] Elzabet Healing Stream Totem Plakkie +35775
[19:44:33.891] Flaming Head Cinders Plakkie 74587
[19:44:33.955] Cinders Cinders Plakkie 51986 (O: 52437)
[19:44:34.316] Plakkie dies
So he had cinders for 4 seconds and didn't get a single direct heal (even from himself :P). Another one:
[21:06:39.705] Acid Rain Acid Rain Daftpunk 153626
[21:06:41.949] Flaming Head Cinders Daftpunk 116025
[21:06:42.448] Elzabet Ancestral Awakening Daftpunk +33782
[21:06:42.855] Flaming Head Cinders Daftpunk 82875
[21:06:43.762] Flaming Head Cinders Daftpunk 6947 (O: 75928)
[21:06:44.141] Daftpunk dies
Almost no heals at all!
I'd suggest assigning a healer to cinder duty; others should help as well but just tell one guy their absolute prio throughout the fight is focusing on cinder targets; healing and dispelling them. The healers can for sure see cinders debuff on their healing frames and everyone has a bossmod or weak aura that doesn't allow them to miss they have cinders?