We just installed v1.6.3 and noticed some issues with the batch editing function for relationship fields.
Using “Remove all values” and “Replace value” gives a blank screen and no chances are made. The “Add to each” parameter works fine.
Tested on CentOS Linux release 7.1.1503, PHP Version 5.6.18
And on a local instance (XAMP).
We do not see this problem on our test installations. Try setting display_errors = On and see if there's an error message in your install.