Parece não haver informações que o liguem ao roteiro real da vida real.
Uma citação descobri (sem recursos) que:
The heavy, block style was inspired by a font used on a 1940s Czech propaganda poster.
Só para ficar claro - enquanto a linguagem em si é para ser relacionada ao latim (veja abaixo), letras individuais NÃO eram bem alfabeto latino. Em vez disso, eles eram símbolos que poderiam ser traduzidos para letras latinas através de um simples código de substituição (mostrado na imagem).
Artigos antigos no Wiki (Seção do idioma e do sistema de escrita) diz (ênfase minha) :
The Ancients' language appears to be a precursor of Latin, but it is still distinct. There are many similarities between the two languages, and someone with a decent knowledge of Latin may, given time and practice, be able to understand Ancient as well (src: "The Fifth Race")
A citação exata do episódio (do SG Wikia):
As Daniel pointed out while Jack was still under the influence of the Ancient Repository: "The language he's speaking has similar sounds to medieval Latin but it's still quite different." (2.16 "Fifth Race").
Dicionário está na Wikia.
... Além disso,
Passages written in Ancient on the shows can be transliterated into English (there are no characters for spaces and punctuation marks). These transliterations show that the in-show writing system rules do not necessarily apply in reality, but they sometimes reveal in-jokes or offer further (non-canon) information instead. For example, parts of the writings on Atlantis main screens include the beginning of the nursery rhyme Where Oh Where Has My Little Dog Gone?, and the text shown on Daniel's laptop in the episode "Affinity" can be transliterated into "Actual words are hard to deciph(er) so this(')ll work".
Playback supervisor Krista McLean said that when she originally put the graphics together for the Atlantian holo screens, she carelessly used things that were going through her head. When fans translated the language on the internet, she became more careful and tried to not use direct English translations anymore. (src: Hey, Look Who Wasn't Trapped Under A Refrigerator For The Past Two Months After All! Stargate Playback Superviser Krista McLean Finally Drops In To Answer Your Questions.". Josephmallozzi's Weblog. 2009-02-10. Retrieved 2010-05-21.)