1: In my research institue, the official evl letter only from HR with fixed format. Such as Mr. is working as xxx(title) with salary xxxx. Will this kind of letter works?
-It may not be enough.
3: Also it is wierd that in PJian's letter, "This letter is to support pjiang's Application for Adjustment of Status, based on an Approved I-140 Immigrant Petition.". In the case of NIW, do I need somebody to support my I485. And how the new boss know the area of his I-140.
-Pjiang's sample letter is enough even if it is for your NIW. You of course need somebody such as your employer's EVL to support your I-485.
4: What I am thining to attatch the paper I published after I140 petition, and the official EVL from my HR to prove I have a job, and my suerpervisor's letter to prove my area. Then I will write a letter to let the VO know: what is the area of my I140 claimed, publications, and the EVL letters. Will this work.
-This will be perfect for your RFE response.