[NTG-context] Custom lua script (updating and debugging)

Hi list, I'm currently messing around with a custom lua script (a pretty printer) and I have some beginner trouble. First: I put the file in "MyContexDir\tex\texmf\tex\context\base\". What do I have to do to let ConTeXt work with the script and to let ConTeXt know that something has changed in the script? Is "context --generate" enough (after initializing with "setuptex.bat")? Second: How can I debug errors in my *.lua file? Just put print("debug message") in the function that is (supposed to be) called? Any help appreciated and thanks in advance! Stefan