1) Add dbprefix in advance option
2) Time zone America/New_York
3) download latest.zip and be1cb2d9-ed05-2d81-85b4-23282832eb84.zip , take url from index.php of koken installer
4 ) extract latest.zip and create elementary folder in storage/themes/
extract the be1cb2d9-ed05-2d81-85b4-23282832eb84.zip file and move to storage/themes/elementary folder of extracted latest.zip
5) PHP REQUIREMENT LINK : http://help.koken.me/customer/en/portal/articles/827352-system-requirements
6) Release date : http://help.koken.me/customer/portal/articles/848339-release-notes