I'm also having problems getting updated info about WorldTech Devices. According to a Dun & Bradstreet company called Hoovers (they track and rate other companies) WorldTech is located in California. But when I tried going to the listed website I get a "site isn't loading right now" error message.
WorldTech Devices, Inc. | Company Profile from Hoover
Assuming they are in fact out of business, you might be able to find a driver by using Device Manager, updating or uninstalling the existing driver, and let Windows 7 search for a comparable driver. (I'd make sure to have another keyboard available just in case.) Expand "Keyboard" > right-click on the K9852 > Update Driver Software. See if that helps. Or, after right-clicking on the K9852 > Uninstall. Then reboot and see if a driver is found and installed by Windows 7.
How To Access Device Manager From the Control Panel in Windows 7
In the alternative, you could use a 3rd party company like
DriverMax. Let it scan you computer and see if they can find an updated driver.
Or, you could try running the XP driver in Compatibility Mode.
Compatibility Mode