Documents to show evidence of previous employer

Hi,
I am new here, if this question is already answered, please let me know.

The HSMP document HSMP INTERNAL CASEWORKER GUIDANCE V4.0 states that I have to submit employer reference that states information including start/end dates and positions held, job title as well as job responsibilities. I have some questions.

I have worked with 3 employer in the past in India and a current employer in UK for last 1.6 year in total 7 year 4 months. I have a total 2 years work experience in UK.

I can get employer reference with complete detail from my current employer where I work as Senior Software Consultant.

But from the previous employer, I have the employement reference containing start/end dates and positions held, job title and "no job descriptions".

My queries are :-
1.I must get previous employer reference with job description to gain points?

2.If I can get my previous project managers/senior in my previous employer to write "reference letter" with current date and I include these with my back dated employement reference, will this meet the requirement?

3.If I get only current employer reference with complete detail and past employment reference(without job description), will this be a problem to get minimum points?

I have all the salary slip, tax document from my previous and current employer.

I appreciate your help and thanks in advance.

-Pandask