Hi Karel,
If you use the ribbon button to create a work item, it will not immediately show up in the task board. You would have to refresh the task board for it to appear (using the Refresh button in the ribbon). However, if you right click inside the task board and create a new work item using the context menu, the new item will be added immediately without requiring you to refresh.
Unless you're using a date column in your query (which you don't seem to be) the task board does not use dates in any way so I'm pretty sure that the issue is not time zone related.
Also remember to be careful about the states/columns you choose for the task board because in some TFS process templates Bugs and Product Backlog Items have the same states, whereas in others they have different states. If the states are different you may have to go into the task board settings and add all the Bug states that you want to see (see attached screenshot).
It seems that you are using some sort of scrum template, either one from Microsoft or perhaps one of the EMC templates. In the Microsoft Scrum template, Bugs and PBIs have the same states. In the EMC Scrum 2008 (v2) template they have almost the same states, except Bugs include a Ready for Test state. In the EMC 2010 (v3) template the states are completely different (except the deleted state).
Regards,
Joel
the Telerik team
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