David

If the page was created using the Advanced Customization Wizard my guess is that you are attempting to use the client side API or JQuery within code that is executed on the server rather than in the browser.

To confirm that the crm or JQuery libraries are defined and available a quick check is to open up the page in Chrome. You will have to browse to this page within the CRM system to make sure that it loads correctly. Once the page has been opened in the browser and the screen displayed you can open the developer tools (F12) and in the console you should be able to reference both the $ object and 'crm' object.

Just for the record, if I do the above then it works fine.