Develop a musical piece using the given theme and incorporating the letter-based structure provided.
X:1
L:1/8
Q:1/8=232
M:4/4
K:Bb
['FB EB DB']  
X:1
L:1/8
Q:1/8=232
M:4/4
K:Bb
|: B | FB EB DB FB | Dd e/d/c/B/ cC CB | DB FB EB DB | Fd d/c/B/A/ BB, B,B | FB EB DB FB | 
 Dd e/d/c/B/ cC CB | DB FB EB DB | Fd d/c/B/A/ BB, B,B | fB e/d/c/B/ fB dB | cF B/A/G/F/ cF AF | 
 fB e/d/c/B/ fB dB | Fd Ac BB, B,B | fB e/d/c/B/ fB dB | cF B/A/G/F/ cF AF | fB gB aB bB | 
 dB d/c/B/A/ BB, B, :|  