Laser triggered sound (seeed music shield and Photoresistor)

I have a project using an arduino uno, seeed music shield v1 (sucks I know, but had on hand) and a laser pointer and Photoresistor trigger setup.

I got each working separately but when I use the music shield it uses up the serial read so I cannot use the data from the Photoresistor to trigger.

Is there a way to read the value from the Photoresistor without using the standard serial pin or a different way that doesn't require serial read?

I just need to be able to trigger the audio to play when the laser is interrupted/tripped.

I looked at the softserial but even when using in a blank sketch it doesn't seem to work or I don't understand how it works. When I run this sketch it writes "Goodnight moon!" on 57600baud, but 4800baud writes: "ÿïßï"

The softserial sketch used to test:

The 2 sketches I am combining