Sometimes conflicts occur between the ApexSQL Complete hint-list and SSMS’s native Intellisense. In such cases, SSMS’s native Intellisense may overlap the ApexSQL Complete hint-list as shown below:
To temporarily work around this issue, disable native Intellisense in SSMS.
Under the Tools menu, click the Options option:
In the Text Editor list, choose the Transaction-SQL sub-list, from there, select the IntelliSense item and uncheck the Enable IntelliSense check box:
The issue is scheduled for resolution in the next release of ApexSQL Complete R5 2017, planned for the Q1 2017.