TIER1 DEPENDANT VISA - QUERIES

Hi,

Both self and partner are currently in Singapore and are looking for employment in the UK.

While my partner holds a Tier 1 work permit since Dec-2010, I am looking to apply as a dependant to be able to move/work in the UK together. Have the following queries around the same-

(1) Should the main applicant be employed in the UK for dependant to apply? If not, then what needs to be filled up under sections 7.13 to 7.19 (of the VAF10 FEB 2010 form) which is related to the main applicant's details around employment in the UK?

(2) While in the UK in case main applicant stops working, will there be any restictions to the dependant's working?

(3) While in the UK in case main applicant wants to switch to Tier 4 (study permit) at a later stage, will the dependant be able to conitinue working or will he need to reapply either for Tier 1 (independent) or Tier 4 (dependant)?

Would appreciate your reverts on the above.