Multi user plugin v 1.8.2

[Singh]

I have installed getsimple on wampserver on localhost and added the multiuser plugin (& the I18n, TinyMCE (currently disabled)).

To enhance the security I changed the admin directory's name to adminsecret. Now the multiuser plugin gives me following errors:

1. Warning: include(../admin/inc/timezone_options.txt) [<a href='function.include'>function.include</a>]: failed to open stream: No such file or directory in C:\getsimple\plugins\user-managment.php on line 643


2. When adding a new user I am getting the following messages
(a). Notice: Undefined index: users_name in C:\sites\CMS\getsimple\plugins\user-managment.php on line 144

(b). Notice: Undefined index: users_bio in C:\sites\CMS\getsimple\plugins\user-managment.php on line 146

©. Notice: Undefined index: Pages in C:\sites\CMS\getsimple\plugins\user-managment.php on line 148

(d). Notice: Undefined index: Files in C:\sites\CMS\getsimple\plugins\user-managment.php on line 149

(e). Notice: Undefined index: Theme in C:\sites\CMS\getsimple\plugins\user-managment.php on line 150

(f). Notice: Undefined index: Plugins in C:\sites\CMS\getsimple\plugins\user-managment.php on line 151

(g). Notice: Undefined index: Backups in C:\sites\CMS\getsimple\plugins\user-managment.php on line 152

(h). Notice: Undefined index: Settings in C:\sites\CMS\getsimple\plugins\user-managment.php on line 153

(i). Notice: Undefined index: Support in C:\sites\CMS\getsimple\plugins\user-managment.php on line 154

(j). Notice: Undefined index: Edit in C:\sites\CMS\getsimple\plugins\user-managment.php on line 155

User does get created at this point.
Any suggestions on how to fix it up?