The main reason for the introduction of DotNet support in MAXScript was the fact that ActiveX controls which were largely used in the 3ds Max User Interface were made unavailable in 64 bit Windows versions.
Scripts developed for versions prior to 3ds Max 9wwould require a rewrite to be able to run under 64 bit Windows operating systems.
Converting ActiveX ListView Control to DotNet ListView Control
Converting ActiveX TreeView Control to DotNet TreeView Control
[3dsMax Path]\ui\macroscripts\Macro_BakeTextures.mcr
The Render To Texture dialog has been updated to use DotNet ListView controls instead of ActiveX controls.
[3dsMax Path]\ui\macroscripts\Macro_NamedSelSets.mcr
The Named Selection Sets editor dialog has been updated to use a DotNet TreeView control instead of an ActiveX control. It is a good example of using Drag And Drop in DotNet TreeView controls.