Render doesn't stop when using the stop button or closing the IPR window, GPU is still used until all samples are finished.
2/ Initialization problem :
I never could make two different scene work in one Maya session,
I mean I always have to close Maya and open it again to work on a different scene, else IPR is frozen,
maybe this is relative to point 1.
3/ Node Editor:
Playing with the new nodes from alpha 8.0 in Maya node Editor can be really really good

but this experience is only great with two conditions :
- Attribute Editor must be hidden (using channel box)
- nodes must not be created from the "create node pane".
If the Attribute Editor is open, the Node Editor become laggy,
I know that the attribute Editor is a work in progress and I guess the old AE callbacks from V2 are the reasons for the slowdown and for other bugs in Alpha 8.0,
so please get rid of the old code as soon as possible

If nodes are created with "TAB", or with the createNode command, or with the (excellent) Janitor tool from Ivankio, then everything is fine,
the nodes only have 1 output displayed so the connections are quick and straightforward like in Standalone just one drag to connect 2 nodes.
But if the nodes are created with the Create Node panel, the message output is added to the nodes,
so as there is now two output, the connection process is slower again, from pop up list to pop up list... I found that the Create Node panel use the shadingNode command in renderCreateNode.mel to create the nodes (instead of the createNode command),
with this command a hidden connection is added from "message" attribute to type sets (material , texture , light, utiliy , ...) used for the Hypershade section tab...
Not sure how to solve this Maya issue.
Also, shouldn't each different output from the new nodes have a specific data type instead of "apiPointerData" for all ?
this would help maya to minimize the destination pop up list,
or direct connection when there is only one destination of this type.
4/ Attribute Editor :
I know this is a work in progress but, in case this help, I comment on current state:
I was surprised to see icons in front of each attribute, as in V2.
I think this is really an unnecessary piece of the Standalone interface in Maya,
Attribute types (boolean, float, filename, ..) are perfectly recognizable in the attribute editor without (cryptic) icons.
AEtemplates for new nodes seems to be Mel embeded in C++ , do you intend to keep it this way ?
If yes, it's too bad because this is one of the strength of the Openness of Maya,
we user could have help with AEtemplate if they were standard MEL scripts in standard places...
Is it to simplify the install process ?
I found attributes to have strange names,
For example: In the transform3D_NG node, we can find the Oct_translation_x attribute, its UI niceName is Translation like 3 other attributes in the node...
Are this names coming from the Octane API (with prefix and underscore ?) and you have to define niceName for each ?
I was expecting the longName translateX for such attribute, which give for free the Translate X niceName.
5/ Sorry :
I couldn't test yet the Volume nodes

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