I ran the installer:

./qt-enterprise-linux-x64-5.6.0-beta_224.run
qt.network.ssl: QSslSocket: cannot resolve SSLv2_client_method
qt.network.ssl: QSslSocket: cannot resolve SSLv2_server_method

(The SSL stuff is just warnings; modern openssl libs don't include the v2 methods by default, but we still try to load them.) So no relevant output on console. I'm running this in ~/test/release/; and ~/test/ is a symlink to /mnt/test/eddy/, where /mnt/test/ is the mount-point of a separate partition.

The dialogs came up and ran their usual course. I selected ~/test/release/Qt5.6.0 as install directory. At the end, the dialog had a check-box to "Start Qt Creator" and that check-box was checked. I hit Finish; but Qt Creator didn't come up.

I manually run Qt5.6.0/Tools/QtCreator/bin/qtcreator from the command-line and Qt Creator starts without problems.