I tested the same problems with the earlier version 0.98.4 and they do not exist!
Maybe the new QT library or XnViewMP itselfs make these problems.
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1. I started XnVievMP with Browser window.
2. Create a new directory within the current directory (e.g. D:\Test)
3. The directory is created and shown correctly in browser window


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The same problem I will get, if I rename an existing folder and try to open it.

I have admin rights.
Both problems I could test in a previous version of Xnviewmp 0.98.4 and this version works perfect.