When changing the normalization from linear to log, the ClassedColorSlider widget rounds off the values after you drag the handle to the nearest integer. Here is an example based on one of the developer samples. To recreate the issue, check the 'lognormal' checkbox. The widget histogram and handles are updated correctly. Now drag one of the handles. You'll notice that it is always rounded off to the nearest whole number. This doesn't happen if the widget is initially created with the log normal option.
Esri ClassedColorSlider - JSFiddle
In my example, I had to manually set the symbol on the breakInfos returned from the smart mapping response in order to have the intervals colored appropriately in this ClassedColorSlider widget.
Not nearly as important to me, but I thought I'd also report that this widget does not work with the vector basemaps. When you choose any of them in this example, the application seems to do nothing because it is throwing an error. I thought that the vector basemaps were now supported with all of the widgets? Wouldn't it be better to have the widgets fall back to return the scheme for the "streets" basemap along with a warning, rather than just throwing an error and returning nothing?