Move cover page colour and blank coloured end page to doc-specific files. That way output where the colour isn't appropriate, such as Nook or the newly introduced A4Lulu output (which is the A4 book but with white cover page and no end coloured page, and so suitable for using as the content on Lulu, where the cover is separate) can omit the colour.

X: 15
T:Lanigan's Ball
R:Jig
H:Seamus Quinn
M:6/8
L:1/8
Q:3/8=120
K:G
|: "Em" E2E G2A|B2A Bcd| "D" D2D F2G|ABA AFD|
"Em" E2E G2A|B2A Bcd|"Bm" eBB B2A| "Em" BEE E3:|
"Em" e2f g2e|fag fed| "D" e2f gfe|fdB Bcd|
"Em" e2f g2e|fag fed| "Bm" edB cBA|[1 "Em" BGE EDE:|[2 "Em" BGE E3|]