When the COM object does not get instantiated due to a missing entry, adding an entry manually will help resolve the issue.
PLEX: 7.2.1
1) Locate HKEY_CURRENT_USER\SOFTWARE\Classes\Wow6432Node\CLSID, add the following key/value pairs.
Key:
{FFC4C83B-2E32-4997-B1A1-ECACF8CB90D9}
String Value: Default REG_SZ PanelAPI Class
Sub Keys:
InprocServer32
String Value: Default REG_SZ <Full\Path\to\CoolPlexPanelAPI.dll>
ProgId
String Value: Default REG_SZ COOLPLEXPANELAPI.PanelAPI
The Key/SubKey structure will look like this,
2) After adding above mentioned registry key/value pairs, relaunch the application to verify the reported problem.