Gunslinger missed skill category?

[Evershifting]

a) As far as I know, Sawbutcher and another unlockable tinker class both has 2-3 locked categories.
b) One unique Steamgun grants Ceasefire skill

So I think, that due to a bug or something like this we have no access to locked category

P.S. I climbed to level 39 and was killed in dungeons below Gates of Morning

P.P.S. Sorry for bad English

[HousePet]

There is no missing category.

[Evershifting]

thanks =(