New to the forums and TOME, definitely not new to roquelikes in general. I have a few questions concerning version 1.1.2. Having a blast so far, thanks for the game! Not sure about the forum etiquette so sorry if this is the wrong section but I most certainly do want spoilery answers

1) I didn't notice lives increasing in the character sheet after drinking the Blood of Life, is this how it's suppose to be? I'm not sure but I think that one character that drank the potion could go to negative -1 lives when he perished and still came back from the Eidolon plane.
2) I'm I supposed to clear all the tier one starting dungeons for exp and stuff and is there a downside in doing so (besides the obvious of having your character killed if you suck)? Is there a time limit of some kind after which you can't win anymore?
3) I'm playing a skeleton level 19 archmage but I'm not sure I understand the mechanics of Disruption Shield so can someone explain it to me -if it's worth using/learning that is.
4) My other character who is a dwarf reaver screwed up in the temporal rift and died twice (three deaths overall). Character screen tells me that I still have 2 lives left + one quaffed blood of life. Is it possible to win the game dying this early, how many lives people usually need in the Far East and beyond?
5) About saves: If I have a mental save of, say, 5 %, then is it the same as confusion immunity 5 % when trying to resist enemy's confusion attack?
Thanks in advance!