Recently we got a project from a third-party that was rendered with Chaos Vantage and it had some textures with the ".tx" extension. Corona was unable to read that format.
The only workaround that we found (Really simple, quick and 100% EFFECTIVE) is to:
1. Change files extension to ".tif". We used "Bulk Rename Utility" tool to change several maps at once. You can find the tool online, it has a free option.
2. Open Photoshop, go to Scripts - Image Processor... Then just simply save it in the desired format (we saved it in JPG).
3. Then, we used Project Manager 3, under Asset Tracking select the TX files and replace them for the .JPG files.
That's it! Hope can help anyone in the future.