Please email supportbg3@larian.com with your latest save before interacting with the transponder (or post/email/PM a Dropbox or Google drive link, etc), referencing this forum topic.
In Explorer you can zip a file or folder by right clicking on it/them and selecting 'Send To | Compressed (zipped) Folder'.
Each save is a folder in the 'C:\Users\<UserName>\AppData\Local\Larian Studios\Baldur's Gate 3\PlayerProfiles\Public\Savegames\Story' folder. The fastest way to get there would probably be to copy the line below into the location bar in Explorer and hit Enter.
%LocalAppData%\Larian Studios\Baldur's Gate 3\PlayerProfiles\Public\Savegames\Story
EDIT:
The issue with the playtime in named saves is a localisation issue, and I was able to reproduce this problem by switching the language to French.
The act transition may not be related; a couple people have also reported this, but least one person mentioned being in a later area of the game.
The suggestions
in the troubleshooting topic under 'Crash after tutorial, at the end of the nautiloid' may help, if you didn't already try that.
