The first time I encountered this glitch was on Reach, but I had hoped never to have to suffer it after that. For those of you unfamiliar with this glitch, objects (particularly blocks, braces and walls) that have been placed in forge using the coordinates tool will move ever-so-slightly after you save the map. This may not sound like a big problem, but if the objects are on the floor then you end up with a horrible, cracked floor that makes it look like this was your first effort at using forge.
As previously stated, this glitch has been around since Reach and ruined some of my favorite maps. When Halo 4 came out and I heard about forge 3.0, I thought that things like this would be ironed out of the game, but just after I completed my most recent map and went to play-test it in customs I encountered it.
Those unfamiliar with the glitch should also note that 1) as of Reach no one has been able to fix this and 2) going back into the map/readjusting then coordinating/turning off and on Xbox etc. don't work because I've tried them. Another irritating problem is that while you could get around the problem with precision tools in Reach, this isn't possible in Halo 4.
This stupid bug has been in Halo for a good 3 years now and I've seen some of my best work ruined as a result. Please for the love of god fix it.