For Zip files with a large number of files in them, it may take awhile for the Zip file previewer for Windows Explorer to load and display the content. There currently is no way to cancel the previewer during this process.
Previewing a series of large Zip files with the Zip file previewer for Windows Explorer, periodically will not refresh the preview pane correctly.
Encrypted files opened by the Zip file previewer for Windows Explorer are not currently being wiped prior to deletion.
The internal text viewer can take awhile to load and display very large text files. Currently, there is no way to cancel loading the text until it completes.