The original WLOption control – the windowless version of the OptionButton control – exposes a property named Group, which enables you to create groups of mutually-exclusive WLOption controls on the same form. (Controls with same value for Group belong to the same group.)
The .NET Framework platform doesn’t support windowless controls, thus VB Migration Partner converts WLOption controls into “windowful” radio buttons. As far as the .NET Framework is concerned, radio buttons are grouped in accordance with the container they share. In other words, all the radio buttons inside the same container – e.g. a Panel or GroupBox control – are mutually exclusive.
A consequence of this difference is that you might place two groups of WLOption controls directly on the form’s surface, because you could assign them to different groups of mutually-exclusive controls by means of the Group property. These controls would be converted correctly to VB.NET, however they would end up in the same group.
The bottom line: the original VB6 application should always gather WLOption buttons inside visual containers – for example, WLFrame controls – and never have two WLOption controls inside the same visual container if the controls have different Group values.