Epic Fail!!! Of the Combat Type! ((Also question for PRC.)

[paragon_nemesis]

So a friend and I were in a party, we just made some new toons in the underdark. Everything was going fine. Me playing, Favored Soul, him playing rogue. Until he needed a heal. I clicked to cast a healing spell. It queued. then disappeared. So I did it again. Nothing. Moved around the field a bit, to make sure it wasn't lag. All enemies were aggro on him. So still nothing. I hit and kill an enemy. So this time I'm sure not lag. I queue it. It disappears again. So I spam my button. He dies horribly in a fiery death of glory. I follow shortly. We lose xp, we spawn. ((Spellbook was completely full. I just rested before combat.)) Why did that happen? Any input would be appreciated.

On the subject of the PrC. It seems I keep having trouble with different aspects of the same question. (Used to PnP rules, so a lot of the mechanics of this game/server can be foreign to me.) Okay. Part one. Assassin. I have an assassin who has 3 spellbooks as of yet. However, even when right clicked, no time is available. Not worried about it. Looked up the spells and found out how long they last, i.e. Invisibility is 1 minute per level. That's where the problem seems to present itself. Does this go off of my assassin level? Or does it go off of my overall level? How does this work? Thank you for your input ahead of time. Second part. It makes sense, not only logically in a real life situation, but I personally believe that it should be in game as well, as per both PnP rules, and NWN1 rules. Why in the world, when you use knockdown on an opponent do you not gain sneak attack advantage on them? I was under the impression that any time an opponent, (Not undead, ooze or something else of the sort.) is caught flat-footed. Then they are prone to sneak attack. When you knock them down. You attack at their flat-footed AC do you not? Also, real life application. Say you trip a guy. He's laying on the ground. You start swinging two big swords at his face, he's got a big disadvantage and probably won't make it yes? :p ((Just saying..)

[Luna]

For assassin spells, it's your assassin level.
You can take the feat below as well to help augment your level.






Practiced Caster (Assassin)
Type of Feat: General
Prerequisite: Spellcraft 4 ranks.
Benefit: Your caster level for the chosen spellcasting class increases by +4. This can't increase your caster level beyond your HD. However, even if you can't benefit from the full bonus immediately, if you later gain noncaster-level HD you may be able to apply the rest of the bonus.
For example, a human 5th-level cleric/3rd-level fighter who selects this feat would increase his cleric caster level from 5th to 8th (since Cleric+Fighter has a 8 HD). If he later gained a fighter level, he would gain the remainder of the bonus and his cleric caster level would become 9th (since Cleric+Fighter now has 9 HD).