I've noticed that if you try to load more Extension Plugin in RoadRunner, only the sliders handled by the first Plugin are properly displayed.
The problem can be easly solved by this simple change in the RRExtension class:
Public Function ReturnSlider(SLD As String) As Long
'Default (No Action) <== LINE TO BE ADDEDI think it's important to add this change on every plugin developed with the Extension Plugin Interface in order to allow the simultaneously use in RoadRunner.
ReturnSlider = -1 <== LINE TO BE ADDED