Various errors when installing the Wiki Manager UI extension through the Extension Manager

While trying to install Wiki Manager UI extension 4.0 on XE 4.1.3 SNAPSHOT (4.1-SNAPSHOT), I've found the following issues:

• The author is plain wrong (see screenshot)
• The logs are very strange and non explicit (see screenshot)
• The spinning wheel is on an item that doesn't correspond to the conflict being shown (see screenshot)
• I don't understand the conflicts since the documents should be the same AFAIK. FYI the following 3 pages are shown in conflict: XWikiServerClass, XWikiServerClassSheet and XWikiServerClassTemplate
• Clicking on "keep the new version" doesn't save anything. When I check the history there's no change.
• After "resolving" the 3 documents (XWikiServerClass, XWikiServerClassSheet and XWikiServerClassTemplate) I was very surprised to see that the EM asked me again to resolve them! Then Thomas told me that's because I'm on a multiwiki... Nothing was shown. The current wiki on which the extension was installed was not mentionned anywhere and I only needed to install on the main wiki (and not on other wikis) but I couldn't find any option to do that
• I wanted to cancel the operation since I don't want to install on all subwikis but I couldn't find any cancel button!