What does "INIfile" mean as I can not find it anywhere in the docs.
INIfile is the full path to a configuration file that contains info your program might need. I included this code in the sample because I figured you might need to handle a configuration file in your final code.
The error is probably because the file is missing in the folder where the EXE file exists when you are running it in debug mode.
The INI File that I included called MyConfigSettings.ini is assumed to be in the same folder with the EXE file. The CopyFile setting in the Build Settings should copy the sample file to the same place the EXE file. Based on how you set up your folder structure is probably the issue.
For now just comment out the call to the INIfunctions.GetKey in the App.Open event.
Welcome to Xojo!
Now, just a few housekeeping points to keep in mind:
In the other thread, @Norman P gave you good advise. Once you study and try things, ask specific questions. This community is among the most helpful around. People here will help. You will get the best answers when you ask clear and well documented questions, where you show what you tried and clearly describe your issue.