Windows 7: Gigapocket TV tuner drivers for Windows 7?

Hi all,

I'm trying to upgrade from XP to Windows 7. My PC is a Sony Vaio PCV-RZ504 with a TV tuner: Gigapocket.
I used the newest software available from Sony, but XP version is available only. Version of software is 5.5
Installing the software is no problem, but starting it gives unexpected errors. Has anybody succeeded in using gigapocket with Windows 7?

Update: last night I managed to install Sony Mpeg decoder software (part of the Gigapocket 5.5 installation kit). No strange low level errors occur any longer. But starting gigapocket generates the message "Unable to locate Sony TV Tuner". Starting the TV Setup tells me that another application is using overlay. Is windows 7 using overlay in any of its components?