I have an OS X Lion guest set up to share the Home folder from the host. This works part of the time, but at times the connection seems to be lost, and the shared folder icon shows the red circle/diagonal warning. Other times the shared folder icon is normal, but no shared files are seen in the guest. So far it appears that rebooting the guest gets it working again. Has this been logged as an issue?
I'm using Lion 10.7.1 as the guest OS, but I'm having several issues with my shared folders. Sometimes I manage to get Read and write permissions, and some times just "custom access". I don't find any ways to control this. Another issue is that large files (> 4GB) can not be copied to the shared folder, instead there is a pop up saying "not enough space" (with is not the case). I have installed Parallels Tools. I don't know if these issues are related to MacFUSE ?
The issue was escalated to second level support a while back, and AFAIK is fixed in the current version.