Special instructions to install MLANP v.1.5.0 or other versions on MAC. The problems are given by the the package Rpanel and bwidget tools, used for some interactive teaching tools; maybe in a future version I will change such interactive tools, because Rpanel often caused problems. 1. Close RStudio or R 2. Find on the web the bwidget tarball file (without installing it). My version is "bwidget-1.9.14.tar" 3. Copy it on /usr/local/lib/ (e.g. from a terminal: sudo cp bwidget-1.9.14.tar /usr/local/lib/) 3. Open a terminal and then give the commands: cd /usr/local/lib/ sudo tar -xvf bwidget-1.9.14.tar 5. Previous step should solve the error about Bwidget 6. Download XQuartz, install it and run it. 7. Open RStudio and then install Rpanel. Now it should work