There should be no problem. You can specify the directory, where the livebuffer should be written to, with option -b. The LiveBufferSize should be a few MB smaller than the size of the ramdisk (because of index.vdr and the 001.vdr gets a little bit larger than LiveBufferSize) and 'Keep paused LiveBuffer" should be no.
Since Reinhard Nissl just released a fix for cvideorepacker, I have removed the portion of the livebuffer patch which disabled it. It seems to be working well now with cvideorepacker enabled. :)
Best Regards.