If you want to use skip logic then you will need to create your form in FormsCentral.
You can get more information on skip logic here : http://forums.adobe.com/message/3763831#3763831
You can also use Conditional Elements.
If you want to start from your docx then you will need to convert it into a PDF form first before importing it to FormsCentral. You won't be able to use skip logic on this form.
hope this helps