Comments: Sound Page Guide
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Layered Image?
Instead of using the capacitive touch library, you could use the default Trigger.ino code on the LilyPad MP3. The issue is that you would need to design the Sound Page based on switches https://learn.sparkfun.com/tutorials/getting-started-with-the-lilypad-mp3-player#building-the-board-into-your-project. One possibility (which can be complicated depending on how it is implemented), is to make a layered image. When the image is pressed, the layered image will make full contact with the traces and act like a switch similar to this online tutorial http://www.instructables.com/id/Fun-circuits-with-conductive-paint/?ALLSTEPS
Alternative Options: Dedicated Capacitive Touch Sensor?
Using a dedicated chip for capacitive touch sensing would be better and easier to use than the Capacitive Touch library. One example is the MPR121 like the breakout board https://www.sparkfun.com/products/9695 . This isn’t ideal since you would need to wire it up using I2C, rewrite the code to trigger the MP3 tracks, and make some sort of adapter to connect the paint to the smaller pins on the capacitive touch’s plated through holes that are broken out.
Another solution is using the Bare Conductive Touch board https://www.sparkfun.com/products/13298. This one is basically an MP3 Trigger but it already has the dedicated capacitive touch MPR121 sensor on the board. It already has the code installed for capacitive touch IC with the circuit.
Larger Resistors between the Send and Receive pins
Talking with our QC department that uses the capacitive touch for our pogobeds https://learn.sparkfun.com/tutorials/constant-innovation-in-quality-control#cap-sense-buttons, they used a large resistor (20MOhms instead of 1MOhm). I think you would need a larger resistor in series to get it working with a more reliable connection. It also depends on the surface area of the pad that is being sensed. You would want a big pad for the Arduino to sense a change in capacitance. They also suggest inspecting the values through the serial monitor as the pins were sensing the changes. They had some issues and had to calibrate certain pogobeds depending on what was being used (high power circuit or low power circuit). Capacitance changes depending on what components are attached and the input power supply.
They also added additional code to debounce (checking the sensor pin once in the loop) I haven’t tested this yet since I don’t have a high value resistor like that in tech support, but this would be more ideal.
Buying the individual LilyPad MP3 trigger will not have the Sound Page code. Make sure to upload code in order for this kit to work => https://github.com/sparkfun/Sound_Page_Kit.
You would need a 5V FTDI and a mini-B cable to upload.