Symptoms
The Multi select control is not being displayed correctly.
Diagnoses
This seems like something went wrong with the DLL files.
Resolution
Starting the K2 SmartForms Control Pack Setup Manager from the Start Menu and selecting Repair then finishing the wizard resolved the issue.
Please note this will also remove any applied coldfixes, meaning you will have to re-apply the coldfixes after the repair operation. In this case, coldfixes specifically pertaining to the K2 SmartForms Control Pack.
