I just switched to the new 64 version. Congrats to Don and everyone else involved on this auspicious milestone!
The "Overwrite Existing Item" dialogue has three buttons: "Suffix", "Overwrite" or "Cancel".
1: When the dialogue first appears it seems to be confused as to which is the default choice. For me at least it puts a dotted selection rectangle on the "Suffix" button, but the "Overwrite" button has a blue border. The <enter> key does not activate any of the buttons.
2: After moving the selection with the arrows keys, the dotted selection rectangle and the blue border then only appear on the one button. After this the <enter> key only activates the "Suffix" button, but not either of the other two.
Not certain this is specific to the 64-bit version though.
Cheers
XYplorer Beta Club