Do you have any idea how to write a program, what code is and what compiled code is ? 59 MB in executable terms means millions of lines of code. Of course, it wasn't just the code, probably 50% of the size was taken by resources.
If bugs you're talking about are all functional, then 59MB would be more than enough to fix them all.
People still don't get the point that this "headstart" still is not the "final" version that you will see on Feb 2nd. In fact even on Steam it still shows as "Star Trek Online Beta". In game exclusive items are still not in game, as is the C Store items.