Browsing through the Alpha. it seems that monsters and NPCs all have extensive, wordy descriptions, and the same stats as PCs. Monsters also have a table with special actions and NPCs potentially have gear and can perform combat maneuvers like PCs.
This is very rich and nice, but it's also a lot to track. I have yet to run the game, but it seems really difficult to come up with NPCs on the fly, or to run combat without bookmarking the right rulebook pages beforehand, memorizing stats and monster strategies.
Is the game really intended to be that prep-heavy or? Is there a simple way to do it or am I overthinking it?
In the alpha you have standard stats that you can use, I have made a NPC-sheet (in Swedish) and written in the stats for the most common foes. If it isn't important that every NPC should be unique I can reuse these easily so for me there has been very little prepping for my two games that I have had. The talents they have can be more of a challenge, but most NPC will have the standard talents so you don't have to memorize everyone.
For the monsters you pretty much only have to keep track of damage and roll a D6 for their actions. Since the PC rarely will battle two different monsters it has been very easy to just flip to the page of the monster and mark their damage on a small note.
TLDR; It may look like lot of prep, but in reality it has been easy for me to do it and I am probably not smarter och better then the average GM.