On beginning your journey into Tolkien's mythos concerning the Men of the West.
Usage of the Lexicon
This Lexicon is not intended to be a complete replacement for Mr Strack's Eldamo, most certainly not at this early stage of compilation. Instead, its main, current function is to act as an enlarged dictionary, housing both original and neo-word formations, along with some grammar articles expanding on known knowledge to cover more situations than one can necessarily extrapolate from the original grammar.
It also has an ever expanding list of names for people to use for anything from fiction to real life, just make sure to talk to the speakers on appropriate choices or on making new names!
Which version of Adûnaic is adapted for the Lexicon?
For the newcomer, there are in fact three conceptual stages of Adûnaic as Tolkien revised his approach to the native tongue of Númenor. The stages are lettered as follows: k-, d-, and a-Adûnaic. Being focused on the Classical period of Adûnaic (right before the fall of Númenor), the lexicon is based upon d-Adûnaic, which also has the greatest source on grammar for the language. It would indeed be better to use a latter evolution of the language whenever possible, but that is unfortunately impossible in this case, since a-Adûnaic has too little information, and what information there is frequently contradicts earlier writings for no apparent reason. That said, there will be influences of a-Adûnaic within the work, since it is not entirely exclusive of earlier works. For those worried about its influence, do not worry as it will only appear as addendum rules concerning prepositions and long vowels in special situations.