I have tried to download the new flash player on my macbook pro 13" retina many times. Downloading is not the issue it is installing. I am able to start the installation, I am then prompted to close safari once the installation has reached 50%. I quit safari properly, closing safari improperly is not the problem. After I quit safari the installation continues it reaches about 55% and then stops. Once stopped it looks like this:
Help would be greatly appreciated!
If you haven't rebooted yet, that's a great place to start. At minimum, it will eliminate a bunch of potential roadblocks for other steps.
If rebooting doesn't help, please see the installation troubleshooting guide:
Collecting and posting the logs would help us improve the product, and the links to the offline installers at the bottom of the guide should get you going.