Hi,
Regarding learning music theory, there is an excellent site called Teoria (
http://www.teoria.com/) which can help you with that.
If you're using Notation Musician or Notation Composer, there are a number of tools that can help you learn to read sheet music (it's helped me tremendously).
Use the Tempo buttons to slow down a piece as it plays, so you can more closely watch the notes as they highlight and hear what they sound like - both pitch-wise and duration-wise.
"Format/Display pitch names in noteheads" will show you the note names, so you can get familiar with where they are visually on the sheet music, and hear them so you know what they should sound like on your guitar or other instrument (scale exercises can help here for "fretboard familiarity".
"Perform/Practice Setup" lets you set up practice loops to work on small chunks of a song at a time. If you do this with a song you already know, then the visual of seeing the note on the score while you're playing it on your instrument will help you associate the notes you see with the notes your fingers are playing.
Enjoy
Sherry