OK.... let's look at several things then.
1) The project that you have open... do you have a code unit called SQLUtilities in the project itself? If so, a script extension with the same object name as the code unit cannot exist. If this is the case, try removing the SQLUtilities code unit from your project and reload the extensions
If that doesn't work...
2) Let's look at the contents of the TCX file. Copy it to an different folder, change the extension from TCX to ZIP, and then open it and show me a screenshot. The contents SHOULD include both the Description.xml file and the SQLUtilities.js file. If not, we may need to repackage.
If that doesn't work...
3) Let's compare the contents of SQLUtilities.js with the Description.xml. It's possible that if you have method, property, etc., names different in the actual code than is what is in the extension, the extension could "error" and you won't see it. Please upload the ZIP file and I'll take a look. See, I see that the TCX file has a modified date of today's date... so, I don't trust that it is EXACTLY as the extension is when you download the TCX file from my repository (which I just did and tried myself and it works). So, something is not matching between the XML and the code file so let's see if we can figure that out.
If that doesn't work... perhaps we'll have to take this off forum and actually have something more on the lines of a phone call or something to debug it.