Quote Originally Posted by Dionysus9 View Post
Dont forget you need the following to purchase the clan skill upgrades:
1) a high enough unit level to unlock the upgrade (e.g. level 5)
2) enough unit skills to unlock the upgrade (e.g. 4 seperate skills)
3) an unspent unit skill point (from recent experience gain)
4) enough clan skill points (e.g. 20) (see avatar page)

I kept trying to upgrade without #3 and/or #4 and thought it was broken-- but you need to have the clan skill points as well as an unspent experience point, as well, plus all the unlocks. Hope this helps.
I'm not talking about the clan skill upgrades - as you can see I've already upgraded my Naginata Warrior Monk with a clan skill upgrade. The bug is that if you attempt to add melee attack to Katana Cav or Yari Cav, it'll let you spend the point but not give you any stats.