AN form query -EU national

Hi All,
I hope that someone was in the same situation and knows the answers to my few questions:
1. As a EU national working continuously in UK for 6 years didn't apply for the ILR as it's not a requirement. My question is what shall I write in the question 1.3 regarding the date when my ILR was granted?
2. Do I need to submit any additional documents confirming my continues stay in UK except the 6xP60 and WRS? like some randoms payslips or bank statements?
3. It does say in the guide as well that the application can be refused if I was absent from UK 5 years ago before my application was submitted. What confuses me is fact that as a EU I need to proof 6 years stay in UK so are they gonna check was I in UK 5 or 6 years ago? It actually makes a difference for me as I was on holiday 5 years ago
4. Can my husband send my application on my behalf while I will be abroad?

Thank you for all the comments