Shaman "path of mork" not working for me!

[Sulorie]

If your gear (like keeper set for example, happens alot) gives you +1 in a tree, and you buy an ability with it, but you aren't technically supposed to get it until you get another mastery point via leveling, the game just gets confused and the ability is only usable in rvr, till you actually hit the level you are technically supposed to use it, could be what is happening here.

According to the bugtracker posts it is a different issue, as just going to rvr is an easy workaround. It sounded to me like it happens without +mastery gear too.

[Rydiak]

Yes, some tactics (and maybe abilities too) are bugged with the wrong level requirement for their mastery slot.

[Sufferkate]

Make sure that you have enough gear in order to have the extra pt.(turns green). Also, they have a trainer at the top of keeps in RVR zones and in the city.