I have a problem with this tuner, in windows 7 x86 it's working good with progdvb x32, but in 64 windows version (and progdvb 64) I get this error: [{BDA} Cinergy C PCI Digital Tuner] Device not started! How can I start the device in 64 bit version? (tuner is working with another dvb software in x64 windows)

Try install ProgDVB not to Program files directory.

I installed in another folder (created by me in C:) and it's working. Thanks. It's a general bug for x64 version, or only with my tv card?
Another question: can plugins work in x64 version (like vplug, in 32 bit it's working if copied in plugins folder of progdvb). The plugins menu show no plugins, even if I copy to plugins directory some plugins.

You need x64 versions of plugins, x64 versions of all codecs and of course good x64 driver.

... to much requirements
I did not know that exist 64 bit codecs and 64 bits plugins (if you know, please share me the name of some x64 codecs and x64 "educational" plugins like vplug, I will search for it).
If I will install the 32bit version of Progdvb on win x64, will work?

Yes, x32 ProgDVB is more simple way