The ExtraButtons plugin allows setting buttons 6 - 20.

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• Enable plugin - When a plugin exists in your addons folder and is loaded, it can still be shutdown from within HealBot options.
• Set spells for - Select helpful or harmful.
  • Helpful - Set helpful spells that will be cast on friendly characters.
  • Harmful - Set harmful spells that will be case on hostile characters.
• Modifier key - Select the modifier key(s) used in combination with mouse clicks.
• Avoid Blue Cursor - Cast an invalid spell and ended up with a blue cursor? this option is your friend.
• Auto Target - Set the healers target to the player/npc being cast against.
• Text Boxes - The mouse button pressed with cast the spell, the binding is a combination of the Modifier key and the Mouse button.
  • Note: if manually typing in spells, check it shows in the tooltip to know its set correctly.
• Auto Trinket - Attempt to use trinkets automatically when casting spells.
• Binds - Bind mouse wheel or keys to HealBot buttons.