Develop a musical piece incorporating the designated alphabet-based pattern and the supplied melodic theme.
X:1
L:1/8
Q:3/8=90
M:6/8
K:D
['A>BA d2 d efg f3 gBB c2', 'A2 A dcd']  
X:1
L:1/8
Q:3/8=90
M:6/8
K:D
|: A>BA d2 d | efg f3 | gBB c2 d | edc d3 :|[M:3/8][Q:3/8=60]"^Largo" d/e/ | f2 d | B2 c/d/ | 
 e2 c | A2 A |[M:6/8]"^NB"[Q:3/8=90]"^Allegro" dcd BcA | BA^G A2 A | dcd Bcd | ede cde | fgf efd | 
 edc d3 :|  