PhabricatorRepositorySvnCommitChangeParserWorker can't process commits which delete a file from a relocate directory (if the directory also didn't exist in the previous commit). The problem is that the relocated directory path doesn't get added to the $add_paths variable so phabricator tries to look up the deleted from in the same location from the previous commit rather than in the location from which it was moved from.
To get an example of this is quite tricky so I've set up a demo svn repo here: https://subversion.assembla.com/svn/phabricator-example/
The basic steps to create your own are:
svn co $some_repo mkdir ./trunk/foo svn add ./trunk/foo svn commit -m "Created directory." svn rm ./trunk/foo svn commit -m "Deleted directory." mkdir ./trunk/foo mkdir ./trunk/foo/bar touch ./trunk/foo/bar/bad-file.txt svn add ./trunk/foo svn commit -m "Recreated directory." svn rm ./trunk/foo/bar/bad-file.txt svn commit -m "Deleted bad file." mkdir ./branches/new-branch svn add ./branches/new-branch svn commit -m "Created a new branch." cd ./branches/new-branch svn merge -c 2 $some_repo/trunk svn commit -m "Merge commit 2." svn merge -c 3,4,5 $some_repo/trunk svn commit -m "Bad commit: merge commits 3, 4 and 5."