No idea if it could cause any damage, but if I were you, I would try to cycle the suspension in FR position and with floater without rear shock spring to observe the internaction. If you can feel any restriction in the movement, or for example the position of brake caliper against the rotor is changing, or anything else worrying occurs - then running such setup won't be a good idea... But if it works smoothly and everything looks ok, I'd go for some ride tests