Hi iForbes,
My guess is that you need the trusted SSL root certificate used in the VCS (not just the intermediate root) installed in the zero client. Typically the next step is to use a tool to inspect the cert chain presented by the VCS and see what trusted root cert is being used. There are on-line tools for cert chain inspection - we have links on the Teradici support site here: http://techsupport.teradici.com/ics/support/default.asp?deptID=15164&task=knowledge&questionID=1087
Alternatively you could open a ticket with the Teradici support team at techsupport.teradici.com and we can help work through this.
Cheers,
Stu
Stuart Robinson
Director of Systems Engineering
Teradici