Bugs do happen, and one of the joys of alpha-testing is finding them !
The crash logs are located in the logs/ folder in .chunkstories ( %appdata%/Roaming ). They are named to the game's startup date and time and contain relevant information about the game's processes and the possible crash reason.
You can run directly the game by going in to the .chunkstories folder and typing
java -Xmx1G -jar chunkstories.jar
into the console. Then you'll be able to see everything the game prints out ( some things are not even in the logs, like partial frametimes in Gbuffers debug mode ) and the crash reason if it does.
The game has an automatic logs upload feature that sends your log ( if <300k ) to our servers automatically when you close it, either by will or by force. You are prompted at your first log-in to opt in or out of this feature. If you choose to opt-out and/or the auto-uploader has issues, you can still email logs at