Symptom
When using the mouse to select an element to, either send backward / bring to back (or bring forward / bring to front) an over lapping value chain element in the editor, the buttons don't work.
Resolution
Currently, this is working as designed. If you are affected by this issue and want to create a feature request, please create a ticket in SAP for Me and reference the ticket number CS-3207.
Current Workaround
Instead of using the mouse to move the value chain elements, use the arrow keys to move the element into position, then the buttons will then work in the toolbar.
Keywords
KBA , BPI-SIG-PM-MOD-EDT , Graphical Editor for SAP Signavio Process Manager , Known Error