Aadieu

Another bug: mayor's stash key turned into a second copy of the sword of spartusia +2!

Can't seem to finish the ruby quest... Game's forcing me to do goblins instead. Or did i miss some sort of exit? BTW, journal is all goblins, too.

I would beg to disagree. Despite some pandering to a teenage audience, few of the characters are at all teenage, and one of the rules of marketing to teenagers is to have a) young adult heroes, b) father-figure types that one can still relate to, c) ageing but young at heart scoundrels (think Skywalker, Kenobi, Solo).

Therefore:

Aerie: elven equivalent of 17-ish
Anomen: 25-27, the man is struggling with himself, trying to turn into a Keldorn-type figure, not to grow his first chin fuzz
Cernd: who knows, who cares?
Edwin: 35+, maybe young-ish 40, reasons include thick long beard (try growing one sometime, few can get one like that much earlier), thieves' guild career, advanced mage skills, weak physical attributes hardly descriptive of a young man, attitudes, clear weight gain (see portraits) between BGI and BGII indicating approaching middle age, dialogue (can be obsessive about power, but not much of a hothead = older)
Haer'Dalis: 30-ish in human years, been to too many places and beds to be a kid, has made a career for himself
Imoen: 20-23, depending on whether she is in fact the younger sister or just takes said sidekick role
Jaheira: 40 human years = 60 as a half-elf, which fit in with her bossy and long marriage and the fact that she was a friend (maybe even an interest) of Gorion's; also, had quite the career
Jan: gnomish equivalent of human 40; eccentric, both old and young enough to have a married former flame
Keldorn: 55 - he is the grizzled veteran, the old yet still strong officer... seen in his interactions with other party members (bit mentorly/fatherly to Minsk, etc.). Also seen in his stats - as the *only* character to clearly have spent his entire and quite long life wielding heavy two-handed weapons and wearing plate armour, he obviously initially had an 18-something strength and high dexterity to survive to advanced age on the front lines of his struggle to reform the world to his ideals. Now, experience compensates him for youth.
Korgan: 40-ish in human years, been around a lot, but no elder and not a leader like Keldorn
Mazzy: typical adventurer, equivalent of human 25
Minsc: 30-35... yes, *30-35*. He is either borderline retarded originally or has suffered severe brain damage, so his arrested development makes sense. Also, Nordic-type societies often had a distinction between 'young-malehood' and 'manhood', with his quest more likely to be for acceptance into the strong and experienced veteran club, not for the right to trade his mum and a wooden sword for his first real weapon and ale with the big boys. Also, with his mental abilities and head injury, who knows how long he has been trying to complete the rites for manhood.
Nalia: 22-25, her demeanour stemming from a sheltered life, not extreme youth
Valygar: 27-30, still a strong young man, but not at all a kid
Viconia: around 30 human years, making her the oldest of the NPCs - harsh, experienced, but nowhere near a matron (even if only because she can still pull off damsel in distress)
Yoshimo: about 27, still a young rogue, but he IS too far from home to be much younger, and he is somewhat known

BTW, let me use this moment to state that Keldorn and Edwin are the best NPCs ever - Keldorn due to access to the ultimate weapon and uber kit powers that make him the number-one spellcaster slayer, and weak stats that can easily be fixed with items accessible almost immediately after getting him; Edwin because he has the firepower of any two other mages due to about double the spells (triple-quadruple at lower levels), comparable to a sorceror protagonist but more versatile and able to die and resurrect lots without the nuisance of reloading