I have completed several plaques now in my brief time with my laser. I suppose I have screwed up at least as much material as average for starting out, but I'm getting the hang of it I guess.
I have found the best way to center text, like on a plaque, is the put your graphic(s) and text on the screen, draw a vertical line that runs through everything, select all graphic(s), text and the vertical line, then do a SHIFT+E to center it. Change the view to snap to a grid and move the entire material to be engraved to the center in both the horizontal and vertical.
However, this does not place things exactly centered. Close, but not quite there. I then nudge things till I get them where I'm happy and am good to go.
Without "nudges" it seems like about 1/16" is the area of probability for the centering.
Is there a better way than I'm doing it?