Was Ted Cruz “at the time of the Adoption of” the Constitution a “natural born Citizen, or a Citizen of the United States?
If you're asking if Ted were born back then would he have been considered a citizen in either form? The answer to that question would be no because he was not born in the U.S. Furthermore, at that time it would have been the citizenship status of the father that would have determined his citizenship, not the mother. Since his father was not a citizen, who on top of it was not present in the country, Ted most definitely would not been considered to be an American citizen, "natural born" or otherwise by virtue of his father.
Had Ted been born in this country at the time the Constitution was adopted he would have been recognized as a "natural born" citizen when and if his father actually became a citizen.
Only those first wave of children who were born in this country to non-citizens, at the time of their birth, and became of age to satisfy the age requirement for Presidency, would have enjoyed this consideration and been recognized as "natural born" citizens. After that period, only children born to fathers who were citizens were considered "natural born" citizens. Children of immigrants who had not obtained their citizenship at the time their child was born, became naturalized citizens when their father became a naturalized citizen. If the father had become a citizen before the birth of his child, then the child would have been considered to be a "natural born" citizen, and his father would still have been considered a naturalized citizen.