Tier 2 ICT Visa Queries

Hi
I have Tier 2 ICT Long Term Visa stamped in 2012 and currently living in London. I am working at a mid-senior level management in a reputed firm in UK. I was told that when my 5 year tenure (2017) will complete if my Salary is > 153.5k there won't be any cooling off requirement. But this seems a long period and I want to explore my options. I have few questions if some one can help & Thanks in advance..

1) If there is another firm who provides me restricted CoS can I change employment without cooling off ? is the answer different if new employer provides Tier 2 General or ICT CoS?

2) Is there any way that a reputed A rated employer can change Visa category for their mid/senior management roles i.e. Tier 2 ICT to Tier 2 General?

3) Does the period stayed under Tier 2 ICT counted for ILR? Does period stayed under Tier 2 General counted for ILR? What is the duration of stay to get ILR?

4) Even if I meet salary criteria by 2017 (153.5k now, I understand it would be much higher then) it would still not be counted towards ILR. Is that right? So what is the possible way in my case so that I may be able to change employment and start my period towards ILR.

Many Many Thanks in advance

Regards