Never heard about novoslovienski language ?
Basically, novoslovienski language is just modernization of old  slavonic language which was created by schollars Cyril and Metod. Language that was started in Thesalonike and than use in the empire of Great Moravia and after fall of G.M was used in others countries, like Bulgaria, Chorvatia, Russia, etc.

I heard of it already. But I must correct you – Cyril and Metod did not create Old Slavic language, they just used the language of Slavic inhabitants living around Solun and then after the arrival to the Magna Moravia they mixed this language with the language of another Slavs living in the empire (Cyril /Constantin/ calls them Sloveni or Slovieni as you like, in Proglas – you can hear the poem in youtube). But Old Church Slavonic language was used only by clergy and in the masses, common people used own language, of course.
They had only created the writing Hlaholika (by official history) and that is also impugnable by findings of older script in Balkan which is very similar to the Hlaholika. I doubt they are inventors of this script.