Link broken.
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You can select your own icon for spells, this is handy for spells like shield or spell reflection, that last a while.
The icon will be shown in the upper left corner when the spell is cast, only applies to spells cast on your self.
The spell type is one of the following:
Caster only, these are spells cast on your self, a heal, recall or resist magic fx.
Area around caster, these are sells that affect targets within a certain range around the caster, it could be damage, or banish spells.
Single target at range, these are spells that affect one target at range, like a force bolt.
Area at range, these are spells that explode on impact, affecting multiple targets, like ice storm or fire storm.
Using the spellmaker you could potentially, make a spell that does area at range heal, not that it would be very useful.
The spell element is either magic, poison, fire, cold or shock.
School as you say, is the skill the spell relies on, higher skill, lower magicka cost.