TwoHandedSword: I have a feeling it's your and/or her spellcasting skill that's the issue here. When she's involved in combat, are the spells listed in her spell book, but grayed out? (Or are they not even there at all?)
First, check your own spellcasting skill, in the lower left corner of the Magic screen. If it's too low, try upping the Skill wand; remember that it takes a number of turns to affect your spell skill. At the same time, try getting Elana to go up a few levels as well; this should increase her own spellcasting ability.
Those other three spells are more expensive than Healing; I have a feeling they're not glitched, but simply out of her reach for now. Also, make sure you have enough mana saved up, especially if she's wandering pretty far from your fortress; there's an extra "hidden" cost to spells when you cast them further afield.
NOT THERE AT ALL sadly. I know how to spot the difference as I also have Malleous and his Flame Strike is listed in his spell book but just cannot be cast yet so is greyed out.
For the "Extra" cost to cast spells in combat that is only for your Wizard NOT your Heroes as the Heroes are "IN" the combat while your Wizard is casting from their Fortress. So the 1x-3x only counts for your Wiz. If you do alot of spell casting make sure to get 4 books in 1 school and the Channeler skill as ALL spells are cast as if they were at home so you never have to pay extra. Plus If you use lots of creature Enchants it cuts spell upkeep by half.
Sadly my Wizards spell casting skill kind of sucks for now as I started the game with the following:
Warlord
Artificer
Myran
2 Chaos and 1 Life/Nature/Sorc Books
Chose High Men as my starting race as they are quite good to start with on Myrror if you start with Adamantium. Adamantium endowed Spearmen are so cheap and powerful and lets not even get started on the insanity that is Adamantium Pikemen and Paladin's.
Oh chose the 2 chaos books so I could create weapons with "Flaming" which gives +3 Atk for only 150 mana.
The Nature book is for Web and hopefully Pathfinding plus Terrain spells to help your city.
Sorc book is for that Floating Island and WindWalking spells along with the pumped up Dispells.
