The only way I have had any luck glueing shrooms
is to let the cuttings sit on the substrate until they attach to a few small pieces. This, of course, won't work too well if you have sand substrate. A shallow bowl with some rubble or crushed coral will work in this case. Once the shroom attaches, you can glue it where ever you want. I have had the best luck with the Ross brand super glue gel. It's available at Office Depot, but I get it at the dollar store...CHEAP
. I have never used veil on shrooms
, but I have had great luck using it on ricordia which are very similar. Anything reefrunner tells you is pretty much gospel though 8) .