The NCI still can be reproduced after replacing in the test case only the icefaces.jar and icefaces-ace.jar from 4.1.1 release, but not from IF4 trunk r. 47097.

I placed the two .war files, one built with the IF4 trunk libraries (icefaces4-portlet-410.war), and another with the 4.1.1 release libs (icefaces4-portlet-411.war) under \\iceads1\Public\users\carmen\ICE-10903\ .

I could not reproduce the NullPointerException nor the NCI popup. For testing I used both WAR files provided at \\iceads1\Public\users\carmen\ICE-10903\ .

On the other hand, after filling and submitting the test form the navigation would not occur. No errors or exceptions would be shown.

Well, it seems the test WARs did not include the correct Liferay Bridge libraries. Both 4.1.1 and 4.0 test cases will work as expected once the following libraries are used:

http://central.maven.org/maven2/com/liferay/faces/liferay-faces-alloy/4.2.5-ga6/liferay-faces-alloy-4.2.5-ga6.jar
http://central.maven.org/maven2/com/liferay/faces/liferay-faces-bridge-api/4.2.5-ga6/liferay-faces-bridge-api-4.2.5-ga6.jar
http://central.maven.org/maven2/com/liferay/faces/liferay-faces-bridge-impl/4.2.5-ga6/liferay-faces-bridge-impl-4.2.5-ga6.jar
http://central.maven.org/maven2/com/liferay/faces/liferay-faces-util/4.2.5-ga6/liferay-faces-util-4.2.5-ga6.jar

Thanks, Mircea, for the instructions on which liferay jars to be used.

Verified ICEfaces 4.1.1 release libraries and IF4 trunk r. 47097 on IE11, FF41, Chrome48 with the attached test app, and none of the errors previously reported could be reproduced; also, the form navigation occurs on form submit.

Verified ICEfaces4 trunk r. 47596 on IE11, CFF41, Chrome48 with attached test case.
The following jars are used:
liferay-faces-alloy-2.0.0-SNAPSHOT.jar
liferay-faces-bridge-api-4.0.0-SNAPSHOT.jar
liferay-faces-bridge-ext-3.0.0-SNAPSHOT.jar
liferay-faces-bridge-impl-4.0.0-SNAPSHOT.jar
liferay-faces-util-3.0.0-SNAPSHOT.jar