Unless someone else can find it consider filing a CASE -
To create a technical or issue case at Cypress -
“Create a Case”
You have to be registered on Cypress web site first.
The USB-Serial configuration utility is part of the install of the USB-Serial SDK Windows Installer & Configuration Utility 20 MB file in http://www.cypress.com/?rID=83110 (now the 2nd entry, but used to be the first) that download and the pdf linked below, require you to login to Cypress.
It only runs on Windows for what is worth, maybe the OP is looking for the tool on a different OS.
Download the USB-Serial Configuration Utility User Guide pdf file (5 entry on the list) for more information and software requirements.
One thing I find lacking on that page is the source code for the Windows SDK, they do have full source for Linux, MAC & Android but not windows.
I guess I could mess with pthreads and libusb and port the Linux one to Windows but then I will have to use a libusb generic driver I guess.
I will open a ticket since I want to use a custom CyI2cWrite function that streams data from a circular buffer instead of giving it a predetermined size. Reason being is that the I2C device (a 12bit DAC) supports a fast write mode and as long as you keep sending data it changes the output accordanly, otherwise I have to send it in chuncks and the interval within writes is too long.
Think of a > 100KHz ARB wave generator using an MCP4725, the delta between writes is 45.4ms with I2C set to 400KHz, each of those ramps is 4096 values from 0 to 4095 with an output between 0V to 5V.