Looks like this thread died, so I wrote one today and added some other things I thought might be nice, wrote it in Powershell and compiled to exe as I had most everything already as a script. Source on my GitHub. Feel free to copy and do whatever you want. To get the full benefit, you'll need PowerShell Studio from SAPIEN. I'd also welcome any pull requests to add more functionality, integrate directly with the host server, and just be generally more user friendly. The links below:
https://github.com/imseandavis/7DTD_Custom_Client_Launcher