RenderDoc
RenderDoc is a stand-alone graphics debugging tool
...I work on RenderDoc myself and you can always contact me with any problems or comments. I'll respond to you directly and personally, and I'm used to helping people with private or NDA'd projects. RenderDoc is 100% open source and development all happens on github. Check out the source and see how any feature is implemented, report a bug you've found, or request a new feature or improvement. Usability matters. Tools should have a low barrier to entry and be easy to use and understand. RenderDoc makes the process of getting started as smooth as possible, and simplifies common workflows. ...