
Agustín Pío Barrios (also known as Agustín Barrios Mangoré and Nitsuga—Agustin spelled backward—Mangoré; May 5, 1885 – August 7, 1944) was a Paraguayan virtuoso guitarist and composer, largely regarded as one of the greatest performers and most prolific composers for the guitar.
This is my transcription for piano of the first movement.

I’ve never heard it played by a pianist. I changed the key from B minor to A minor. The best range for guitar is much lower than the piano. When I played it as written it sounded too low and when I transposed it up a full octave is sounded too high. That is why I dropped the pitch down a full step.