The reason I ask is:
I am just porting over from alpha 4 to beta… and all of the controls I wrote for Nifty no longer respond to mouse right-click (this is code I added that relied on Nifty NOT consuming mouse events).
Basically, if this is the case again… advance UI features in Nifty are now impossible. i.e. Right-click menus… oh… or something as simple as using right-click to open a container in a players inventory.
Anyways… not to be a total downer here… but talk about a HUGE limitation in game design, if this is the case. It’s really no different than not being able to use half the keys on your keyboard 
I think support has changed somehow, maybe its somehow configurable or smth, definitely not out.
I’ll look into this. However, Nifty is getting slower and slower with ever release of JME. I don’t know if it is the insane amount of logging that is being done… of just a poorly written XML parser, but it is becoming a big enough issue that I am looking for other GUI solutions. And I don’t mean parsing XML files that I have written… these are control definition files Nifty seems to want to parse anytime an XML file is loaded or changed (empty or not).
I don’t know if anyone else has done extensive UI work in their projects, but Nifty is unfortunately become THE bottle neck in mine
I think it may be time for me to take a break on this project again. Orge & C++ are starting to look appealing again
The bottleneck is most probably the logging, yeah, theres hints on how to disable niftys logging in the wiki as well (it proved to be a bit more complicated than normal). Actually nifty got a lot faster with the latest stable updates.
And btw, Ogre does exactly the same as jME3, theres nothing that will improve for you. You only add having to care for memory-bugs 
It has the same limitations on object count for example, and on the other its combining different API’s where jME3 gives you everything in a combined way really… and does Ogre even have a built-in gui system apart from whats the GUINode in jME3? You can always go back to just handling quads and BitmapText in the guiNode yourself.
Ogre aside, here is one of the biggest problem I am having with Nifty. While it is loading/parsing/whatever it is actually doing. It locks the render engine COMPLETELY (i.e. Not Responding) until it finishes what it is doing.
Soooo… my options are:
Ensure Nifty loads and completes prior to doing ANYTHING else. (this can take upwards to 30 seconds /boggle)
The way I am loading things now, I was allowing Nifty to do its thing while the scene was loading. Unfortunately, physics start prior to the render engine freezing and everything drops through the world.
In alpha 4, Nifty was loading quicker and this wouldn’t happen.
As for the event consumption, I have been going through the new documentation, and I am not seeing a solution to this issue. As of right now, it seems right-clicks are out of the picture again. This is really unfortunate, as I can not think of an intuitive way of handling inventory containers.
Containers:
Left click should pick up the container
Right click should open the container
Spells:
Right click should write a scroll to your spell book
Right click should un-memorize a spell
Hotbutton bars:
Right click should allow you the choice of opening a script dialog for creating/editing hot buttons
Left click should activate the hot button
Left click (hold) should pick up the hot button to move it to another slot
Items:
Right click should activate associated spells on items
Right click should consume a potion/food ration/water flask
Right click should… etc etc etc etc etc.
This list (in my case) could go on for days
Right click works fine for me. I tried the popup test and I was able to get the popup.
Can you describe your problem more clearly?