Magritte and Pier loaded successfully with one load error:
PRSegmentPersistency>>cleanupSeaside (WAEntryPoint is Undeclared) 

the code is:

PRSegmentPersistency>>cleanupSeaside
"Clear all the entry points that reference other entry points, state and continuations by overriding them with a blank version. Do not try to call #clearAllHandlers because this spawns a new process. Also dump the default dispatcher just to be sure."
<cleanup>

WAEntryPoint allSubInstances
do: [ :entry | entry copyFrom: entry class basicNew ].
WADispatcher instVarNamed: 'default' put: nil

which I think should be changed to:
PRSegmentPersistency>>cleanupSeaside
    <cleanup>
    WAAdmin clearAll

but I'm not sure WAAdmin clearAll is doing exactly what the original code intended