1. Support for Ubuntu is only up to version 9.10 so no guarantee it will work with the newer kernels.
2. All the install intructions will be with the product. McAfee supply debian based DEB files (supported by Ubuntu) in the installer so you shouldn't have any problems.
3. In the release notes there's the line "/etc/init.d/nails status" which i'm guessing will give you details of the service. Assuming McAfee have coded the product with some kind of common sense then the commands "/etc/init.d/nails stop", "/etc/init.d/nails start" or "/etc/init.d/nails restart" would have the desired effect your looking for.
NOTE: My grant number doesn't give me access to the actual Linux installs so these answers are based on guesswork and my linux knowledge.