C20 settings

Hi, I m new to this forum and first time i m working on million dollar script. in the installation file of the script it is given that C20 settings are necessary for the script to run. now when i m trying to run the script, it is giving me installation successful message but it is not displaying the menu in admin panel and also showing error on server on the home page of website. I don't have problem to run the php scripts on server. means i'd tried some sample scripts on the server and that are displaying correct output. this problem is occuring when i am installing this on client's server. Same script is working fine on my hosting where i installed it for testing. Please help me on this problem. does this occurs because of C20 settings???? Please suggest me some solution. Thanks in advance