Urgent Help_for Tier 2 Applicaton outside UK

Hi Gurus,

I need your urgent help to applying for UK Tier 2 visa from outside UK.

My current situations is :-

I'm an Indian national and have a UK Tier 4 dependent visa valid till June 2016, My wife is pursuing Master's degree in UK. I have applied this visa in my home country India last year. Now, I working in Singapore on Employment Pass.

Please help answer my below queries :-

1. As I am an Indian National , Can I apply for UK Tier 2 visa from Singapore

2. I have Tier 4 Dependent Visa valid till June 2016, Which I had applied from India last year, Would it be an effect to my Tier 2 application in Singapore.

3. Being an Indian national living in Singapore on EP, Do I need to submit TB test certificate, because in India we need to submit for six months or longer stay in UK.

Thanks in advance, Please help with your suggestions

Regards,
Rajneesh