We added munchkin code onto our website as it formerly wasn't added correctly, how can I check that its working?
The simplest way would be to go and fill out a marketo form, then visit a tracked page on your site. Go into your marketo instance and check your lead's activity record to see if there is a visit activity.
Don't forget to clear the cookies or open an new incognito window before you do this so you ensure it comes as a new visitor.
There is a chance that you might have cookied already.