Two quick changes (read comments)

Added mouse wheel support to the mode select menu
BGM now interatcs with pausing correctly

load/bgm.lua

@@ -7,6 +7,7 @@ bgm = {
 
 local current_bgm = nil
 local bgm_locked = false
+local unfocused = false
 
 function switchBGM(sound, subsound)
 	if current_bgm ~= nil then
@@ -56,7 +57,7 @@ end
 function resetBGMFadeout(time)
 	current_bgm:setVolume(config.bgm_volume)
 	fading_bgm = false
-	current_bgm:play()
+	resumeBGM()
 end
 
 function processBGMFadeout(dt)
@@ -70,13 +71,20 @@ function processBGMFadeout(dt)
 	end
 end
 
-function pauseBGM()
+function pauseBGM(f)
+	if f then
+		unfocused = true
+	end
 	if current_bgm ~= nil then
 		current_bgm:pause()
 	end
 end
 
-function resumeBGM()
+function resumeBGM(f)
+	if f and scene.paused and unfocused then
+		unfocused = false
+		return
+	end
 	if current_bgm ~= nil then
 		current_bgm:play()
 	end

main.lua

@@ -259,11 +259,15 @@ function love.joystickhat(joystick, hat, direction)
 	end
 end
 
+function love.wheelmoved(x, y)
+	scene:onInputPress({input=nil, type="wheel", x=x, y=y})
+end
+
 function love.focus(f)
-	if f and (scene.title ~= "Game" or not scene.paused) then
-		resumeBGM()
+	if f then
+		resumeBGM(true)
 	else
-		pauseBGM()
+		pauseBGM(true)
 	end
 end