Currently having trouble downloading anything from the exchange or from the s3 online store.

CRC errors do generally suggest that something is very wrong on the server (EA's) end, and your testing on the results that you could get with Dashboard sounds like it would confirm that. Likely the only thing you can do is wait it out and see if it gets better after a while...as in hours or possibly days.

I think the only other thing you can really test is whether you can download things from other, non-EA sources successfully. If the problem follows you around, then we have to consider that something may wrong with your Internet connection or your hard drive.