[VirtualTestCenter - tcl-script]: stc_int::salApply: CUnMappedPortError Unable to find msgr for port

Dear Madam/Sir,

We are in the process of migrating our test-setups to Spirent Virtual TestCenter.
Currently, we are observing a re-occuring, cryptic error-message as we executing our automated test-pipeline. I've went through the installation- and automation .pdf-documents, provided in the Virtual TestCenter-installation, searching for the stated error-message, however, without any findings so far.

Virtual TestCenter setup:
TestCenter VM, version: tmos-5.39-2206
TestCenter client-framework: stc_5.31_Linux_32bit.tar.gz

Note, a version-mismatch between the testcenter vm and the stated client-framework.
Q: Is it possible to download a matching client-framework package, matching 5.39, at the Spirent support-pages? Just to rule out possible version incompatibility-issues.

The stderr-output, generated at the client-side, is as follows:

RuntimeError in apply: CUnMappedPortError Unable to find msgr for port Port 10.76.105.26/1/1 //1/1 (offline)
    while executing
"stc_int::salApply "
    (procedure "stc::apply" line 2)
    invoked from within
"stc::apply"
    (procedure "apply" line 2)
    invoked from within
"apply"
    (file "BgpSimulation.tcl" line 49)

The tcl-script (+.xml) is successfully executed in our previous Spirent TestCenter-setup environment, running the former client-framework 4.40 (hardware-based TestCenter-chassis).

Thanks for all hints/advices in advance.

Kind Regards,

Andreas Nilsson
Test/verification, ND SatCom Products GmbH