[Ready! API 1.7.0.] Gouping Assertions result in Java-error

Hello Support Team,

Today I've updeted to the latest version of Ready! API 1.7.0. Now I'm working on two assertions within a group, so that at least one assertion must evaluate to VALID to assert a group PASSED condition. After defined both of the assertions in the Assertion Teststep, I can select both and click the Group Assertions Icon. After setting the operation and clicking OK-button, notthing happends, no activation of "Assertion TestStep window".

When I look in the (clean) Ready! API-log after this, I see this exception below: 

Wed Apr 20 14:50:06 CEST 2016:ERROR:Uncaught exception in Thread "AWT-EventQueue-0":
   java.lang.NullPointerException
   	at com.eviware.soapui.impl.wsdl.teststeps.assertions.GroupAssertion.configure(GroupAssertion.java:241)
   	at com.eviware.soapui.impl.wsdl.teststeps.AssertionTestStep.groupAssertions(AssertionTestStep.java:375)
   	at com.eviware.soapui.impl.wsdl.panels.teststeps.AssertionTestStepDesktopPanel$GroupAssertionsAction.group(AssertionTestStepDesktopPanel.java:159)
   	at com.eviware.soapui.impl.wsdl.panels.teststeps.AssertionTestStepDesktopPanel$GroupAssertionsAction.actionPerformed(AssertionTestStepDesktopPanel.java:142)
   	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
   	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
   	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
   	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
   	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
   	at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
   	at java.awt.Component.processMouseEvent(Unknown Source)
   	at javax.swing.JComponent.processMouseEvent(Unknown Source)
   	at java.awt.Component.processEvent(Unknown Source)
   	at java.awt.Container.processEvent(Unknown Source)
   	at java.awt.Component.dispatchEventImpl(Unknown Source)
   	at java.awt.Container.dispatchEventImpl(Unknown Source)
   	at java.awt.Component.dispatchEvent(Unknown Source)
   	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
   	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
   	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
   	at java.awt.Container.dispatchEventImpl(Unknown Source)
   	at java.awt.Window.dispatchEventImpl(Unknown Source)
   	at java.awt.Component.dispatchEvent(Unknown Source)
   	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
   	at java.awt.EventQueue.access$500(Unknown Source)
   	at java.awt.EventQueue$3.run(Unknown Source)
   	at java.awt.EventQueue$3.run(Unknown Source)
   	at java.security.AccessController.doPrivileged(Native Method)
   	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
   	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
   	at java.awt.EventQueue$4.run(Unknown Source)
   	at java.awt.EventQueue$4.run(Unknown Source)
   	at java.security.AccessController.doPrivileged(Native Method)
   	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
   	at java.awt.EventQueue.dispatchEvent(Unknown Source)
   	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
   	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
   	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
   	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
   	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
   	at java.awt.EventDispatchThread.run(Unknown Source)

Any with suggestions to solve this?