To save your password for autologin with OpenVPN so you do not need to enter pass every time you connect is quite simple see below. Works for android rooted devices too.
WARNING:Saving your password is considered insecure so please ensure your OS or device is encrypted and your comfortable with the risk.
First go to your server opvn file you want to auto connect to and open it with notepad++ or similar. Find the line with "auth-user-pass" and change that line to "auth-user-pass pass.txt" Now in same directory as the opvn file create a new txt file named "pass.txt" Now open "pass.txt" and on first line enter username for vpn login and on second line enter password. Save and close.
Now you got autologin you can do this with any all server opvn you need enabled.