Symptoms

In K2 workspace when accessing K2 Workspace > Process Overview > Process Instances for particular process you may run into default report display limitation of 1000 rows (as it will be indicated in the top right corner of the screen by the message "This report has been limited to 1000 rows").
 

Diagnoses

This limit is configurable setting which can be adjusted if necessary by editing OOBReports.xml file.
 

Resolution

To increase this limit you have to adjust RowLimitRecordCount value as necessary in "C:Program Files (x86)K2 blackpearlWorkSpaceSiteOOBReports.xml"

Open the file, locate and edit following line:
<RowLimitRecordCount>1000</RowLimitRecordCount>

For these changes to take effect you have to perform IIS reset.