You need to configure impersonation. Impersonator's account will have sufficient privileges for non-privileged user to execute required tasks - for example list sessions, shadow users, etc. With proper impersonation even guest accounts should be able to do this. Please check on-line documentation: http://www.ishadow.com/Docs/iShadowHelp/Impersonator%20Configuration.html or use documentation provided with your installation.

As an option, we can offer no-cost support with your evaluation via WebEx session - please provide us with your contact information and the most convenient time to set it up:
http://www.ishadow.com/tabid/72/Default.aspx