Develop a musical composition using the outlined alphabetical depiction of the structure and the provided theme.
X:1
L:1/8
M:4/4
K:Dmix
['d>efd cAAc', 'A>BAG AB c2 G>AGF ECEG A>BAG']  
X:1
L:1/8
M:4/4
K:Dmix
 d>efd cAAc | BG G2 cA A2 | d>efd cAAc | BGAF D3 D | d>efd cAAc | BG G2 cA A2 | defg abag | 
 fde^c d3 d || A>BAG AB c2 | G>AGF ECEG | A>BAG ABcd | cAGE D3 D | A>BAG AB c2 | G>AGF ECEG | 
 A>BAG Adde | Tfde^c d3 d ||  