1)in manual installation set the path of the  logs and upload_area directories in config.inc.php as :
$tlCfg->log_path = '[[softpath]]/logs/';
$g_repositoryPath = '[[softpath]]/upload_area/'; 

2)use same root user  database credentials for 
(Define database User for Testlink access:)

3)Take database dump after logging in with default username and  password (i.e admin and admin ) and setting 
First Name ,Last Name ,Email ,password from admin panel

4)Remove inserts from [[dbprefix]]events, [[dbprefix]]nodes_hierarchy, [[dbprefix]]testprojects and [[dbprefix]]transactions tables and change auto-increment.

5) Keep $tlCfg->config_check_warning_mode = 'SILENT';

6) Since 1.9.16 make manual installation on Whm1144 server where mysqlnd is enabled.

7) Delete DEFINER=`test835`@`localhost` from SQL.

8) REQUIREMENTS LINK : https://github.com/TestLinkOpenSourceTRMS/testlink-code/tree/testlink_1_9_20_fixed#3-system-requirements---server

9) "_" Restriction of Dbprefix Removed since 1.9.19

10) We use PHP 7.2 as mentioned in the requirements link. Since the script throws syntax error on PHP 5.5 to 7.0.