I had had people ask for Getty before so perhaps I should give in and add it to the list.  I agree the lines between the sites are sufficiently blurred that there is no strict 'macro' or 'micro' site anymore.

Yes 50 credits means 50$.

I'm not sure about paypal address. Try to click "Covnvert credits" and enter your paypal address there.

I'm still not sure where people get the sentiment that you need to "keep up" with SS. I haven't uploaded much to SS in the last few weeks and nothing has changed except an uptick in downloads. I don't think there is some conspiracy where SS down-rank older images and give favoritism to newly uploaded images.

I think it has more to do with other images getting more downloads, so they move up the rankings as opposed to SS move images down in rank to make place for newer images. It has everything do with competition and people need to accept the possibility that others may have better images than you do, causing your download numbers to suffer.

Two weeks is way too short a time to be worrying about sales.  Different images sell at different rates on various agencies.  On average it looks like the action on FT is about 25% of what it is on SS according to the poll on the right.  For you, zero sales on 100 images in two weeks is normal.  My experience is that images often get DLs faster on SS but FT picks up eventually.  For me, I usually earn from 2-7 cents per accepted image per month at FT, which I assume is low.  If yours sell at the same rate then no DLs in two weeks with 100 images is about right.  Once you have 1000 for a few months you will have a better idea.

It was Sep 14, 2013.
I had 869 files in my port by that time. I started contributing to SS in Sep 2012.