Compose a piece of music that adheres to the specified alphabetical framework and includes the provided theme.
X:1
L:1/4
Q:1/4=100
M:4/4
K:Bb
['A G']  
X:1
L:1/4
Q:1/4=100
M:4/4
K:Bb
"Bb" B2 A G | F3/2 G/ F2 | B2 c d |"F" c3 z |"Bb" B2 A G | F3/2 G/ F2 |"Eb" G2"Cm" c"F7" A | 
"Bb" B3 z |"Bb" d2 e d |"F" d3/2 c/ c2 |"Gm" (B d) c B |"D" B3/2 A/ A2 |"Eb" (G B) A G | 
"Bb" G3/2 F/ F2 |"F" F2 F"F7" F |"Bb" F3 z |]  