Depending on your housing design, you may not need the holder glued to the star. If you do need to glue it, pretty much anything except "superglue" will work. Most "superglue" type products release fumes that can leave a frosted coating on optics and LEDS. There is a type made for optical use. It is listed as "low bloom". Most use silicone. The best is "odor free" or "neutral cure". Most silicone sealants release acetic acid fumes while curing. This has been known to cause corrosion on solder joints and circuit boards. Hot glue gun, epoxy, urethane, etc. are all fine with varying degrees of permanence.