I'm having much the same issue. I tried the above suggestions, rebooted and the problem persists. I have a screen capture of what it used to look like but I can't upload a photo here. All I can do is try to describe what that print looks like:
There are two major sections: The upper one has two tabs that are always present; Search & Groups list. When I click on a nzb it shows the files in this upper section under a new tab for each nzb I click on. A slider is on the right of any of these tabs if the data has more lines than the top screen allows at one time.
The lower section has 4 tabs; downloading files, failed files, files list & Logging. When I click on files to download they automatically go to the lower tab and I can see their progress.
I've never had a problem with the fields disappearing and becoming something different but now the search window fills the entire view from the upper toolbar on down. I can click on different views from the toolbar like "downloading files" or "failed files" and they show up as individual windows but not as tabs. I've tried to arrange the windows so I can work with them but clicking on a new nzb and I have to shuffle windows around to see the files to download.
I have a backup disk with all the newsbin files & replaced the newsbin.nbi and then restarting newsbin in hopes that would recreate the Newsbin desktop but no.
Since completely uninstalling and re-installing fresh does not restore to the way it was, are there any specific files I can transfer from the backup that will allow me to get back what was? This was a surprise, I've been using Newsbin for many years and never had this happen before.
Thanks.
P.S.: I want Newsbin to look like it does at 30 seconds in on this video
https://www.youtube.com/watch?v=Bg2jvnqG2jU and all I* have is just one huge search window.