What is the relationship between sampleset and project?
From Array Suite Wiki
The same sample set can be run and added into multiple projects, and multiple samplesets can be added into a single project.
The sampleset meta data will be added into project meta data if user is running pipeline to create project during sample registration. Usually, users are running sample registration with [pipeline] section option AppendMode=Replace. It will use the current sample set meta data as project meta data. Occasionally, user may want to register a second sampleset and run the same or different pipeline (different ScriptID) with [pipeline] section option AppendMode=Append. User will get a project with data from two samplesets. However, the project metadata is based on the latest one. New ones replaced old ones in the project.
SampleSet and project metedata format is defined by default.template