Re: unravel two doesn't save at all
Problem solved.
It ended up because of system locale problem. My Windows username is in Chinese so the save path ended up included unsupported unicode path and couldn't being find.
I follow the instruction (https://www.tenforums.com/general-support/20884-how-do-you-change-language-settings-non-unicode-programs-win10.html) to change system locale to Chinese and problem solved!
Hopefully this could help with people who are struggling with this as well.
To Unravel Team: It would be better if the program could crash or having error message whenever it can't save instead of silent failure.