Craft a musical piece that abides by the prescribed structural guidelines and the given theme.
X:1
L:1/8
Q:3/8=50
M:3/8
K:Cmin
['G/ c=Bc']  
X:1
L:1/8
Q:3/8=50
M:3/8
K:Cmin
 G/ | c=Bc | d/e/ c>d | efe | d d>G | c=Bc | (d/e/)cc/d/ | efe | dd z/ G/ | c=Bc | (d/e<)(cd/) | 
 cBA | GG>G | c=Bc | (d/e<)cd/ | efe | dd z/ G/ | c=Bc | (d/e<)cd/ | cBA | GG z |]  