I am a French player playing with an AZERTY keyboard, so my key to move forward is Z. I don't know if it will do the same issue with an QWERTY keyboard and W key.
I've noticed that when I am building an object (or moving it), I can move in any direction but not forwardly.
I've tried to remove all the key assignation in the options (not movment keys) to be sure there is no conflict with another key in building mode, and the bug is still there.