We've made a two dimensional filter statistics portlet using:
filter:
Status: 10-Novo, 20-Odprto, 21-OdprtoPon, 30-Plan, 40-Izvedba, 50-Test (our statuses)
Assign To: lukas

xAxis: Project

yAxis: Status

When I click on a link the issue navigator displays issues having statuses from 10 (the first) to the one I have
choosen.

This must be an error with the links:
<a href="/jira/secure/IssueNavigator.jspa?reset=true&statusIds=10&statusIds=20&statusIds=21&statusIds=30&statusIds=40&statusIds=50&assigneeSelect=issue_current_user&statusIds=50">50-Test</a>
(this is copied from the portlet's HTML source)