@Derek....
OK so the Summon Ignys spell is definitely not playing it's effect. It's missing the bolded line here in the SpellDefEffect:
<SpellDefEffect>
<EffectName>E_FireballExplosion_Particle</EffectName>
<LocalPosition>0,0,0</LocalPosition>
<EffectScale>3</EffectScale>
<EffectDelay>0</EffectDelay>
<SnapToTerrain>1</SnapToTerrain>
<PlayOnAllTargets>1</PlayOnAllTargets>
</SpellDefEffect>
That appears to fix Summon Ignys at least.
I've done some testing.... and it seems that Summon Shadow Warg and Summon Ice Elemental do not play their SpellDefEffect particle. If you add a <Radius>1</Radius> then it starts working. So it seems (as suggested by DsRaider) that there might be something bugged where the SpellDefEffect particle doesn't play for a summons where the radius = 0.
I guess the fact that is only affects a couple of spells (Shadow Warg and Ice Elemental are all i've found so far) is not such a big deal, however....
I know mods are not so much a concern, but it's a real bummer for my Summing mod (http://fallenenchantress.nexusmods.com/mods/1870) as everything works pretty well except the tactical summons don't play particles 
Would be fantastic if someone could take a look at it.
