to mirror a assembley

1°

I can't mirror my assemblies.

When i try to mirror another object i just draw (like a square or triangle there's no problem.:shock:but when it's an assembly he doesn't do a thing

At first i thought that nothing was happening because i selected the red baseline to,but that wasn't it.

So if anyone has this problem to and knows why help me please,

2°

my machine(to be more precise, autocad Civil 3D 2009) stalls(not responding in taskmanger) when i delete a curve from an alignement.

sometimes i can delete one curve but with the second one it's Banzai

It's not a mather of patience or a slow machine ,it just stalls,

is this a bug