Basic Assembly and Setup

I am completely new to Bittle, just finished assembling one for my grandson. Currently at calibration stage, downloaded and installed Desktop app on my Macbook running the latest OS. App launches, but it is slow and halting, and frequently does not respond to any clicks on the firmware or calibrate options. I did grant it permission and sometimes one or two of the servos move and the board makes a sound, but I cannot get the program to run smoothly. Any ideas?