Hi, thank you for the feedback, means much to me ;) The problem is with the boxes not being placed in the correct slot. The slots assigned to the boxes in VR Builder vanished after building the program to apk. I'm not sure why ;( Only after placing all objects in the correct slots, does the game proceed with plus sign and so on. You can try to find a place for boxes according to the walkthrough, and if the box snaps to the correct place, it changes orientation to 90 deg.