So what you are saying about the new Civil3D is that the wisest thing to do with it is not install it?
For my purposes, it is probably an unnecessary release. There are some new features I would like to try, but not enough to commit the entire office to using 2007 just to keep our drawings compatible. Everybody higher than me on the company pecking order uses AutoCAD like it was release 9 and stop just short of suggesting that the whole office might be better off if that is exactly what everyone was using. We are, and and this is a real quote from our design engineer yesterday "throwing stuff up on a wall to see what the city will let us get away with". In such an environment, most of the functions of even Land Desktop are unused. The only reason Civil 3D was tried was a problem with design changes not being fully updated throughout the drawing set - apparently the risk of errors is less threatening than losing the ability to fudge the drawings to make them look good and deal work out any problems in the field.
Now here's an oddity. I have the Civil3D Companion with my LDD package. So far it appears to work fine. BUT then, I don't use a LOT of that package.
It sounds like the package you have is the Land Desktop thrown in as a courtesy with the Civil 3D. With this release Civil 3D was intended as the replacement for the Civil Design and Survey packages. I think Survey may be dead now and the old Civil Design can still be had for the die-hards, but under its own license and subscription for a sizeable bag of nickles. As far as its working correctly, good for you. Perhaps you held your mouth in exactly the right way and used all the curse words in proper order. Be cautious though because sinc's problems are being reported by numerous others.