The nightly build has been updated with a minor fix to the SMARTSViewer node, which forces the node to only accept SMARTS columns, following a bug report showing that sdf cells could also be selected.
The original version of the node has been deprecated, so existing workflows using String Cells as SMARTS input will continue to work, however, new workflows will require Strings to be passed through the Molecule Type Cast node to cast to SMARTS before the SMARTSviewer node.
I will post a comment in a few days time when the stable builds are updated, assuming no problems arise.
Steve