2. For the second part, if the H-1B extension gets denied, Yes, I will still be holding my current H-1B, but in fact, it is of no use to me because I will be working for a different company. In that case, the only option left for me, I think, is using EAD.
3. Do I have to wait for the H-1B transfer be approved or I can start working for the new company as long as I have it submitted?
4. As long as I am still in the same IT field, doing software, my green card application should be safe, right? my current job (Technical support representative) involves answering customers questions on our company's products, helping them installing/using/configuring/ our products, but the new job will be just installing/using/configuring (IBM) products, and will not be dealing with customers. Is this counts as "similar" too?
This Green Card is such a long and painful process :((
But I really appreciate your great help to me on this path.