There are only a few differences between installing in the wall and in tiles:
STRENGTH OR AGE OF THE TILE
If you have older tiles, you may need to reinforce the installation first. In doing so, I recommend the low-tech approach. Even though there are dozens of companies out there selling braces and metal frame solutions, all you need to do is to make sure that your tile will hold the speaker. I use hardboard (think pegboard without the little holes) as a backing plate. You can cut a piece the full 2′ x 4′ or just a smaller overlapping piece and put it on the back of the tile first.
It’s not really the fault of the speaker as that’s what it does: it moves in and out, creating motion in the frames above. Use patience to listen and pad the areas that need attention.
Take a look here for some basic knowledge about ceiling tiles that you may not get from the manufacturers of the tiles: www.acousticalceilingtiles.net