Healers can heal from below, some casters can also LOS from the wall, keep the minis toward the edge of the platform toward the wall.
Only three group members can go up to each mini.
tank and melee should go.
The wave mobs drop four different types of clickies, make sure the group collects all twelve (3x4) before any clicks are done.
Also make sure the three that click used the same colored clicky