First of all the double continue is not good.
- It means that the installeur didn't manage to connect to the database regarding the information you gave.
The second error is relative to the database too.
- Are you sure that your database postgres 8.x is running ?
- Did you create a database for LibreSource ?
And for the path error, in the setting even if you work on windows, it's better to use / otherwise you will need to double the back-slash.