1)Choose login method : md5 in manual installation
2)While manual installation don't use a trailing slash for absolute url(i.e[[softurl]]) in '* Root' path 
(script adds it while detection and we don't use it in settings.php file).
3)PHP REQUIREMENT LINK : https://github.com/phpcollab/phpcollab/releases . (7.2.0 mentioned in composer.json)
(Check this in next version, as vendor has mentioned in the link regarding version 2.6.4 i.e: this release required php 5.6+.There may be issues with lower versions of php).
4)we have configured .htaccess to comment php_value, as it causes 500 internal server error on panels.