We are marking the 
ClickType column in AdWords API and Scripts reports as incompatible with the following engagement and video-related fields in version v201607 and earlier:
  - AverageCpe
- EngagementRate
- VideoQuartile25Rate
- VideoQuartile50Rate
- VideoQuartile75Rate
- VideoQuartile100Rate
- VideoViews
- VideoViewRate
- AverageCpv
These fields refer to engagement and video view interactions, and aren’t compatible with the ClickType column, a click interaction metric. This restriction is already enforced in v201609 reports, see 
our migration guide for more details.
Starting Dec 1, 2016, you will get a 
ReportDefinitionError.INVALID_FIELD_NAME_FOR_REPORT error if 
ClickType column is requested with any of these fields.
Questions? Visit us on the
 AdWords API Forum or our 
Google+ page.
 - Anash P. Oommen, AdWords API Team
 - Anash P. Oommen, AdWords API Team