VBA Problems after RIS build

We have a standard RIS image (Windows XP SP2, Office 2003 Std) for a
particular type of PC. We have just applied this to a PC and installed
Acrobat, MS Project and Asta PowerProject for a particular user. When we log
in as an administrator everything is fine. AS an ordinary user, however we
get errors whenever scripts create filesystemobjects or applications try and
load vba macros. This doesn't happen on our other PC's. We can't see how the
installation of the extra apps could have changed the permissions.