I mean which part of the game did you try to save when it crashed? Is it in the first shrinemaiden scene, when you try to enter the shrine for the first time, etc.?
I think this is a browser specific error on your PC. Are you using Chrome? It might be blocking third-party cookies/data so it's preventing you from saving. To find the setting, open Chrome settings, type "third" in the search box, click the Content Settings button, and view the fourth item under Cookies. There should be a "block third party cookies and data" option and you should uncheck that and then restart your browser.