How to add folder into mega menu

Dear Sir:

Since this is another issue so i add a new topic!

I found in the plug in, under theme, I only have the folder Default Clean, so I copied the folder and renew it as other theme name, then it crash the whole system. I want to know:
1. If I have the multi store license, when I install the plug in, I still have to create the folder under the theme?
2. If so, how can I add the folder, copy the default theme and rename? is that the right way?

Thanks for your reply
Best regards,

Hi,

What is the error you are getting ? You can check it in your System -> Log.

Also, take a look at this forum post. The case is very similar to yours. 

Every plugin is themeable and comes with the styles for the corresponding theme. These styles are in the Theme folder that you can find in every plugin. If you are renaming/cloning some theme you should clone the theme folder for the plugin as well.

Hope you understand me. 

Thanks