using TFT shield SPFD5408 free pins

Hello everybody

I recently bought this shield on aliexpress :

--> Link to the shield <--

Chinese stuff, hard to make it work finding the good libraries...
But finally it works and i started writing some code to use it

My project is to link it with another board in order to monitor and control the robot I'm trying to build
For that I want to initiate a serial communication using digital pins 0 and 1

For the moment I'm just trying to make a button in order to light a LED (just testing the pins) and here comes the problem :

Both D1 and D0 pins are always in the "HIGH" state...
Nothing in the code refers to those pins but what i wrote myself (and even without those lines, the state is still "HIGH")

I tried to plug the shield without those pins (binding them...) and it works the same

So i guess that the problem is in the library ?
I found this in one of the files (SPFD5408_Adafruit_TFTLCD.cpp)

// LCD controller chip identifiers
#define ID_932X 0
#define ID_7575 1
#define ID_9341 2
#define ID_HX8357D 3
#define ID_UNKNOWN 0xFF

It seems to be something using the pins (useless because the shield works without them)
But when I delete the lines, compilation doesn't work :confused:

Can someone help me understanding that ?