Iยดm wondering why it takes so long to fix this problem, which was reported early in mid-December.
Going back to SP1 isnยดt quite a good solution, because when you reverse back youยดd be faced with the "multiple groups massively slow down the viewport" problem. If you do the xform-modifer and collapse, you loose the stack and the instance. You could save down to a former version, loose all the nested layer structure, do your thing, re-open in max2016 and continue. Not nice.
Best workaround somebody mentioned before: Select the mirrored object(s), go to the Hierarchy panel and press "Reset:Transform".
This is a serious bug which makes working with the program useless when you donยดt know a workaround. After getting the second ServicePack months after release! Who is responsible for this? And weยดre in the second month this bug occured! Where is the fix? Is the programming team too busy with version 2017?
I do archviz work in a small studio, how are you supposed to work reliably with this tool under deadlines? It leeds to the question who takes care of proper beta testing the software under work conditions. Surely no serious workers in the customer business.
Autodesk-Shareholders, you think thatยดs good stock value?? And soon with version 2017, same procedure as last year?