Installing metapackage with fai.me

Hello,

When I want to make an iso on fai.me using metapackages like games-finest or junior-tasks, the underlying packages are not present in the iso and are therefore not installed.
Are there any limitations to the use of these packages in fai.me (perhaps a limitation on the size of the generated iso?) or am I missing something?

Regards.

-- 
Jean-Mathieu