No, No, No.......I've used it several times today.
See here:
http://msdn2.microsoft.com/en-us/library/ba77s56w.aspx
First, load your project in Visual Studio 2005, then:
1.) Make sure E&C is enabled for VB projects.
Tools->Options->Debugging->Enable Edit And Continue (checked)
2.) Make sure that Visual Studio is loading AutoCAD when you debug.
3.)Your project must be in "Debug" configuration.
4.)'Project' Menu->"Project Name" Properties->Debug->
a.) Start Action set to "Start External Program:"
b.) "C:\Program Files\AutoCAD 200(6/7)\acad.exe" or whereever autocad exists on your machine, as the external program.
c.) you can include command line arguments to i.e. load a drawing you like to work with, load a script to "Netload" your dll, etc...
d.) Not too sure 'bout this one, but on my machine, "Enable the Visual Studio hosting Process" is checked.
e.) Close the Properties window "Saving" changes when asked.
5.) Set a breakpoint on a spot you want to stop code execution
6.) Debug->Start Debugging (OR) F5 (OR) Click the Play button
7.) The debug session will start and AutoCAD will load into the debugger process (required for E&C).
8.) Net load your DLL into the AutoCAD session if needed
9.) execute your command in AutoCAD. Execution will stop at the breakpoint you set in step 5.
10.) Modify some code. There are some limits as to what can be modified (check above web page for details)
11.) you can use the "Set Next Statement" menu item (under debug) to reprocess changed code.
12.) Hopefully it works for you now.
What version of VB.NET 2005 are you using BTW?