I'm trying to download El Capitan from an older iMac. I need to download it to use on my MBP. Since it is an older computer it won't let me download form the app store. I just want to download it and put it on an external drive and try to install it on my MBP that way. Is there a way to make it download? I tried holding the option key when clicking on the download. My MBP will not install through recovery mode or with the original OSX disc.