H1B, H4 Visa

Hello All,

I need to attend the interview in Chennai for my H1B visa and need some help and guideline as my documents are not ver clear. My employer had submitted for my Visa procession in April 2013 and I have now received I-797 form and need to schedule an interview in Chennai US Visa office. The problem is my employer submitted the documents in urgent and ask me to prepare the work experience documents of my previous employer by myself and also informed to change my resume and roles and responsibility in the document of the current company. Now I have employment documents of previous employer and the current employer. However there is some difference in the roles and responcibility provided my current employer. I want to know the following.

1. Will the Visa Officer have the access to the documents that was submitted my employer in USA while igniting the Visa processing.
2. Will they verify my work experience with my employer.
3. Should I take the work experience documents that was submitted by my employer in USA [which was prepared by me] or should I take the correct employment documents that I have just received from he employers now.
4. I couldn't get document from one of the previous employer as I was terminated. Will the be a problem.
5. I also had a gap in work, I was not employed for 3 years as I was doing business. Would this be an issue?

I would appreciate if you guys respond to my question and help with some guidance about this.

Thanks