standard pvc purple primer and cement works just fine, just give it a chance to really cure, and then fresh water rince it once before putting it into your system, other than that, thats all i do..
just use the plain ol cheapo white pvc and then either paint it, or put some wireloom chaif strip stuff over it, that way you can allways rearrange...
you can hang the skimmer inside the sump, if it'll fit and stuff, i dont see a problem with that...
my question is left to right, is the intake for the skimmer on the left or right, and then the output is ?