The Star Control mainframe will initially not display the numbers for installed and total star cores correctly, as the text replacement data for them hasn't been set.
Solution:
OnActivate block with
AddTextReplacementData("DLC04GZ_StarCoresInstalled", DLC04GZ_StarCoresInstalled)
AddTextReplacementData("DLC04GZ_StarCoresTotal", DLC04GZ_StarCoresTotal)
or call
StarControl_UpdateTextReplacementData()
in DLC04GZTrackingQuest