Gemini88,
I think your query is specific to a form that is not applicable to you . For eg: ''Additional dependant/declaration'' form is to be used only if the principal applicant has more than 5 dependants . In your scenario, if you have less dependants , then you do not tick the document checklist pertaining to this form hence do not include it in the application pack.
but as Kanamen quoted earlier, if there is any section in a mandatory form that is not applicable to you , please do not leave it blank but instead type/print NA .
I hope this information helps.
Sanity