Python and therefore PsychoPy® is CASE SENSITIVE
To use a dollar sign ($) for anything other than to indicate a code snippet for example in a text, precede it with a backslash \$ (the backslash won’t be printed)
Have you entered your the settings for your monitor? If you are using degrees as a unit of measurement and have not entered your monitor settings, the size of stimuli will not be accurate.
If your experiment is not behaving in the way that you expect. Have you looked at the log file? This can point you in the right direction. Did you know you can change the type of information that is stored in the log file in preferences by changing the logging level.
Have you tried compiling the script and running it. Does this produce a particular error message that points you at a particular problem area? You can also change things in a more detailed way in the coder view and if you are having problems, reading through the script can highlight problems. Reading a compiled script can also help with the creation of a Code Component