Edit->Alignment works fine here, using the latest conda build.
OS: macOS 10.14
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.18.15972 (Git)
Build type: Release
Branch: master
Hash: 4e973324ae03c6db9188c08483232fa059c1c9ae
Python version: 3.6.7
Qt version: 5.6.2
Coin version: 4.0.0a
OCC version: 7.3.0
Locale: English/UnitedStates (en_US)