The error means that the CW100Auto.dll is not registered, for whatever reason.
I am providing the format and some instructions for doing this yourself below - but recommend you consider calling tech support to review the situation with them. I have seen other posts out on the web for this issue, some for other products and some for Sonar (8.5.3 and X1), so they may well have a quick answer for you.
In the event you want to try to manually register the dll:
Hit Start, then type in cmd, and when you see the CMD prompt show up in the results, right-click on it and click on Run as Administrator.
Once you get to the command prompt type in:
regsvr32 <path & filename of dll or ocx>
which for you would be: regsvr32 C:\Program Files\Cakewalk\Shared Utilities\CW100Auto.dll
Then hit enter, and it will register the dll.
Type 'exit' to close the CMD prompt session.
Please proceed with above preceded by some sort of tequila, and again,consider calling tech support as this error should not occur during installation. On the other hand, you have already trashed the install, and this will not hurt any other part of your system - it is a program specifically provided by Microsoft for manual registering and un-registering DLL's.
Bob Bone