Tier 1 extension form queries

[Gob00st]

Hi everyone,
I am trying to extend my Tier1 and filling out application form.
I have 3 question:
1>
I am not sure if I need to include information of my lost passport ?

Note: My current tier1 visa is on my current passort only, but my lost passort
has some of my expired VISAs including entry clerance 6 years ago.

2> Regarding my address.
I have
<1>
Lived 1.5 year in my current address
<2>
Lived 1 year in my previous address
<3>
Lived 2 years in my previous previous address

Which ones do I need to put on the application form?
Is it 1> and 2> would be enough(as it covers 2 years in total) or I have to put on
1> ,2> and 3> ?

3>
But I am a bit confused with B11 and B14.
B11 Home Office reference number
B14 Points Based System migrant reference number

Can someone who filled this blanks please help.
I cannot remember if there is any correspondence, maybe one when I receive my initially Tier1 back?
And can I find both numbers for B11 and B14 there?
If I lost that letter, would leave them blank be ok?

Can someone pleaes help.
Thanks
Gob00st