hey man. i would advise against glueing your pieces, but that's up to you. you might find you'd like to move something for any number of reasons and if you glue them you are stuck. as for the colt question, i think you need to try to attach it to a small frag of rock. you can glue it with super glue gel or use a needle and thread method and strap it to the rock til it attached on it's own.
you can look at my sig to see what i have. everything grows nicely and has thrived. i just got the green brain. all my polyps and the colt are growing at rates that i can frag a few here and there. i've found different successes with different locations of each. most of my stuff likes strong to moderate currents, which is good in my tank. i have lots.
you will have to do some research on what you have, what it prefers, and then experiment from there. just give each new location a few days to see how it does before you decide to move it somewhere else.