Preconditions for realm abilities

[FU]

I noticed that i cannot skill certain realm abilities.
Its not clear to me, which precondition has to be met and i do not remember from live.

It would be great if the status message for the training action could give a hint instead of just writing "You do not have enough experience to learn X"

I haven't found so far a good source of information.
Would anyone care to give a tabular overview of the preconditions for different RAs?

[mwrightmgt]

Any RA in brackets [ <name>] can only be trained once you reach level 40