Hi, I tried it out. Renaming the folders won't work as cygwin would just create another one.
The way to make it work would be to rename your Windows username to one without spacing through Control Panel - > User Accounts.
After that, run cygwin and type mkpasswd -l > /etc/passwd
After that, restart cygwin and they'll create the user that is the same name as your Windows one.
Just a reference to others who might get into the same problem!