A workstation takes up all available Concurrent licenses when it is launched. All free licenses in the License Manager get the Running on <name of workstation> status.
You can fix this problem by installing an update.
1. Stop the ABBYY Lingvo 12 Licensing Service on the computer on which ABBYY Lingvo 12 License Manager is installed.
2. Replace all files in the folder ...\Program Files\ABBYY Lingvo 12 License Manager\License Server with the files from the archive from this article (click the LM_update link above to download).
3. Launch the ABBYY Lingvo 12 Licensing Service.
4. Launch the workstation that took up all of the Concurrent Licenses.
5. Open ABBYY Lingvo 12 License Manager and check if the licenses have been distributed correctly.