Putzing around with building my first character, I discovered that the character manager will not acknowledge the prerequisites being met for the following paths, as per the rule book:
Doctor
Gearsmith
Investor (accessible only via inventor/ locksmith combo)
Machinist
Martial Artist
Mystic Healer
Pit Fighter (works with Jack of all trades but not brawler)
Unmovable Aegis (does not work with dark witch)