Installed the LibreOffice_5.3.3_Win_x64.msi on a Windows 7 machine (64bit) which had been running 5.3.2 (32bit). Appeared to install correctly, but on opening any document in Writer, the doc opens and then hangs if any attempt to scroll or resize the window. There is a Not Responding message on the header and everything hangs until Libreoffice is killed in TaskManager. Removed LibreOffice_5.3.3_Win_x64 and installed LibreOffice_5.3.3_Win_x86 Exactly the same symptoms. Ran LibreOffice(Safe Mode) in each of the more aggressive cleanup modes and the same symptoms. Ran LibreOffice after rebooting Windows in Safe Mode (minimal). Same symptoms. Eventually rolled back to a restore point just before the LibreOffice_5.3.3_Win_x64 install, so back to LibreOffice_5.3.2_Win_x86 which had been running. The restore brought everything back to normal.
Maybe testing Menu/Tools/Options/LibreOffice/View - Graphics Output. Changing OpenGL status and if it doesn't work hardware acceleration.
It appears that the test file was in some way corrupt, so it was not a valid test. The same issues occur in the 5.3.2_x86 version which I had rolled back to.