Symptoms

OOB K2 Worklist control provide functionality which is very close to K2 Worklist in SharePoint, but there is some differences and limitations. K2 Worklist for SharePoint (one which can be found on Process Portal) works only with SharePoint 2010 and older browsers, whereas K2 Worklist control leverages features available in newer browsers and compatible with them.

Starting from 4.6.9 support for IE8 has been dropped for K2 smartforms, so Worklist control requires you to have IE9 or newer and compatibility mode set to IE9 or higher.

This may force you from old K2 for SharePoint web parts to K2 Worklist control in certain scenarios.
 

Diagnoses

 After some research on the K2 Knowlegde base

Resolution:

In addition to what was said above you may have other questions about this control:

1. Is it possible to rename the titles of the columns in the Worklist control? This is not possible in current versions of K2 (4.7 or older). There is an existing feature request for this (internal ID 699634)

2. Is it possible to save multiple filters, as it works in K2 Worklist for SharePoint?(https://www.k2.com/onlinehelp/k2blackpearl/userguide/4.6.11/webframe.html#K2_Worklist_Configuration_-_Filters.html).

This feature is implemented in 4.7 and there you can set extra filters in control properties system wide, i.e. for all users.

For 4.6.11 the only way to get similar functionality is to build custom control either on your own or with help of K2 professional services.

3. Is it possible to make the search function, search on all results, instead of only the shown elements? Both in 4.6.11 and 4.7 as a number of work list items grows larger, "Load N more items" link appears on the bottom of the list, and though search does searches through displayed items only, it also shows you "Search More" link to allow searching beyond visible items - see screenshot attached.

Additional considerations: Starting from 4.6.9 support for IE8 has been dropped for K2 smartforms. This introduced number of issues, especially for clients running SharePoint 2010 which forces IE8 document compatibility mode on all its pages via master page, which makes even newer versions of IE work like IE8. Some of SmartForms features have dependencies on features/functionality available only in new IE version and those are not available in emulation mode.

This may force you to change default document mode for SharePoint 2010 to IE=10 to resolve SmartForms issues. Such change may cause minor issues with SharePoint 2010 itself as it relies on/expects IE8 document mode (this has to be tested separately).

At the same time, setting higher document mode also "breaks" default K2 Worklist web part for SharePoint 2010 - which shows endless spinner in such configuration, but it can be replaced with form + Worklist control which gives you relatively the same functionality as web part. Workaround for environments with SharePoint 2010 and K2 4.6.9 or newer is to use form with Worklist control instead of K2 Worklist web part for SharePoint 2010 and raise default document mode for SharePoint 2010.