I'm having trouble getting this working too.
Very simple seteup: MCE2005 machine, and trying to record live TV to an RC1 WHS, and then watch it back.
I followed the guide once and seemed to get it working, and also put the batch file in, but following a restart of the WHS and MCE, it doesn't seem to work any more. MCE reverted back to looking on C: for it's Recorded TV, and even though the server address is showing in the registry of the MCE machine as a watched folder, the DVR-MS content that is already there is not appearing in the Recorded TV menu in MCE...
Looking at the WHS though, all the settings in the walkthrough still seem to be there.
Also not sure if I'm being stupid, but when following through the instructions, I do NOT have a share tab when I right-click on the Recorded TV folder in WHS. I have "General / Security / Previous Versions / Customise". Why are there references to a 'sharing' tab which I don't have?!
Edit: Just ran through the steps and it's working again - am petrified to reboot either PC again now for fear of losing everything again :)