Well I copied the files:
avcodec-51.dll, avformat-51.dll and avutil-49.dll to C:\windows\system32
DGAVCDecode.dll to C:\Program Files\AviSynth 2.5\plugins
And the plugin load without any problems.
But I got some problems with files that dont have a MOD 16 resolution and files that was encoded with more than 1 slice.
Video with non mod 16 resolution
http://img152.imageshack.us/img152/1587/video01bh7.jpg
Video decoding error with AVCSource on a non mod 16 resolution
http://img152.imageshack.us/img152/2619/error01rw9.jpg
Raw 264 file download of the non mod 16 resolution file
http://www.mytempdir.com/1228817
Video encoded with two slices
http://img152.imageshack.us/img152/104/video02vh7.jpg
Video decoding error with AVCSource on a file encoded with two slices
http://img81.imageshack.us/img81/2011/error02do9.jpg
Raw 264 file download of the file encoded with two slices
http://www.mytempdir.com/1228821
Thank you very much for this AVCSource filter it is really more fast to decode H264 streams than using DirectShowSource. This filter just need some little fixes to work perfectly ^_^