Theoretically, what you need to do is run mt.exe ^{Side-by-side Assembly Development Tools (Windows)} to add a bunch of .manifest files before packing with cavapackager

sxstrace.exe can help to diagnose failures in the starting of applications due to SxS misconfiguration.

update: cava docs say some stuff about it MS Windows Private Assemblies and http://www.cavapackager.com/appdocs/projecttree-executables.htm

update: when you ship you can also ship ..\..\bin\diagnostic.exe helloworld.exe for some verbose debugging/diagnostics

good luck :)