We don't recommend loading multiple displays at a time.
I can't speak to the 99% "hanging". If you saved directly to your thumb drive from the web, that may have been the browser copying it to the stick after temporarily downloading to the computer. SkyView checks the database for validity before it loads, so you can't load a bad database if it's corrupt. Most of them are between 2.2 and 2.5 gigs though. If the file on your stick is in that ballpark, it's likely all there.