to control vertices in constructor simply select the vertice selection at the bottom of your screen in the centre next to faces which is just next brushes
(the 3 big buttons)
you cannot make concave models in constructor so dont try to use it like blender milkshape 3dsmax or maya it is a .dif modellor for building architecture.
if you want complicated architecture unfortunatley your going to have to get good with the brushes.
you can however import static meshes into constructor but i wouldnt advise doing so as it may affect your exporting.
dts models can easily be added to a model in worldbuilder i would suggest going that way around.
keep things simple with constructor until you become a pro you cannot load the editor up and suddenly gain godly powers.
check out my site if you would like more advice on anything constructor related.
http://sites.google.com/a/visionsdev.com/billbops-brain/Homeor email me at
Billbop@Visionsdev.com
there are plenty of tutorials on my site far to much information to scribble down in here.