downloded nC 1.20 and uploaded to my server

I have uploaded the files and folders via FTP, everything looks good but when i work on the installation I'm getting the following errors:

nopCommerce installation
The WIN3\IWPD_216(whnow) account is not granted with Modify permission on folder D:\inetpub\vhosts\windowshostingnow.com\httpdocs\. Although this is not an error, it's highly recommended that you configure these permissions.

have to options test again or skip had to choose skip and that takes me to first step:

tick Install nopCommerce and click next typed in SQL Server name or IP address, user and password click next,

second step:

DB information typed in clicked next

third step

An error occured: There is already an object named 'Nop_Customer' in the database.
Running scripts from file: D:\inetpub\vhosts\windowshostingnow.com\httpdocs\install\Scripts\nopCommerce_createDatabase.sql

Yes you probably need to change the security on the files and directories as detailed in the manual.
A

can i have a link to the manual area that i have to work with

will the nC1.90 documentation works for the nC 1.20?