I recently downloaded PSE7 and PRE7 for my home computer. Downloaded the files, unzipped, ran installation and it went smooth. Launched photoshop and played around a bit, closed it, launched elements, did the same. Next morning I woke up and tried to open them. Both of them said "Liscensing for this product has stopped working, if you downloaded the files, please re-download them and re-install" (Not exact transcript, I'm at work, but...that's the basic message). So I re downloaded and re installed (After an uninstall of both products and all their files, including the FLEX one) Still says the liscensing has stopped and to redownload.
Forgot to mention, I bought both of them from the adobe store, so yes they are legit copies =p.