Question on dependant visa application for work permit holde

My partner is a work permit holder since 2009 under FLR(IED) as the application was submitted before Nov 2008. I am currently under Tier 2(general) and am intended to switch to the dependant visa under my partner.

1 - Is it possible for me to apply in UK now for the dependant visa under my partner?

2 - According to the guide for FLR(IED) after april 2010 I need to fill in the form FLR(O) am I right? I am confused as according this link (http://www.ukba.homeoffice.gov.uk/ukres ... ormflr(0)/) does not specify that FLR(O) can be used for work permit holder dependant application

3 - We are unmarried partners and I am not sure for some of the requirement for evidence specified in the FLR(IED) guideline:

• evidence that any previous marriage, civil
partnership, or similar relationship, has
permanently broken down;

We both have not married before and I don't know what exactly do we need to provide?

• you have been living together in a relationship
similar to marriage or civil partnership for two
years or more;

Do I need to provide evidence for 2 years period BEFORE my partner has been granted work permit (i.e. 2007 to 2009) or for 2 years BEFORE I have submitted my application as a dependant (i.e. May 2008 to May 2010)? As we might not have lived together for 2 years at the time my partner has got the work permit.
I guess bank statement or council tax bill should be fine right?

• documents showing joint commitments, such as
bank accounts, investments, rent agreements or
mortgages;

Can I use Council tax bill or tenant agreements with our names on them?

• letters linking you to the same address; and,
• official records of your address, such as your
National Insurance card or health card.

4 - Is home office very strict on the format of address? say my address has got 2 postcode variation and my documents have got both postcodes?