The Nash started the evening three points above the drop zone with this one plus three more games to go.
A win would virtually assure their place in the division and they started well when Oliver Thornley's powerful strike opened the scoring after 16 minutes.
But Boro battled back to level 5 minutes before half-time when Luther Wildin cut in, leaving defenders in his wake. He played a one-two with Kairo Mitchell and the Antigua & Barbuda international struck the ball home in off the post.
Wildin was involved in Curzon`s second goal on 68 minutes when he was shepherding the ball behind, but he knocked the ball out for a corner and from that set-piece, Tom Elliott brought James Baillie down in the box and he dusted himself down before converting the resulting penalty.
However, a minute into stoppage time, Nuneaton equalised when Billy Daniels` long ball in to the area was met by Kevin Langmead, who watched the ball come over his before hitting a stunning volley that flew into the bottom corner of the net.