The movement buttons intersect with the inventory bar which causes an issue. When i want to use the button to walk right it wont work and instead I mine blocks. It works fine when it is set to a smaller size but it is hard for me to use at that size. I always set the button size to 90. My suggestion is to try fixing it by moving it up more or just make a setting on where you want the button to be placed. I hope this gets fixed in a future update.