Systems not showing up in FCS Management Console

I have about 60 computers that I'm deploying FCS to via two policies. These
are a mix of servers and mostly Tech workstations, although several other
non-Tech systems have the client deployed. These systems have FCS
installed and active but only 27 show up in the FCS Management Console. New
systems will pick up the policy when I add them to the deployment group, and
prompt for client installation, but never report to the console after FCS is
installed. All requisite WSUS updates install on these systems as well.

I think there might be a conflict between FCS and my more recent install of
System Center Essentials 2007 (SCE), as none of the systems that have had
the FCS client installed since SCE was installed report their status.

My configuration is as follows:

Workstations are both Vista SP1 (x86 & x64) and XP SP3 x86.
Servers are 2003/2008 (x86 & x64).

Two server FCS config (1 server running FCS SP1 and separate WSUS server)
Separate server running SCE 2007, with its own WSUS server. This server was
added after the FCS system was set up.

All servers and Tech workstations are tied to the SCE WSUS server, with all
other District systems tied to the main WSUS server via GP settings.

Only some of the servers are currently being monitored by SCE, clients are
not (and will not be) monitored via this application.

Both of these applications are in the testing stage, with FCS slated for
full deployment to 1700+ workstations during the summer.

Any help/ideas would be greatly appreciated..