The current version (126.96.36.199, %LocalAppData% reset after update) is downloading a file over and over again.
The file is complete (validated with 7-zip) but at 100% the progress bar is gray and the following error message is displayed above the progress bar:
The GOG Downloader couldn't write to file Z:\gog.com\might_and_magic_6_limited_edition\Might_and_Magic_VI_OST.zip
Seems to be a problem with the verification process.
The log contains two times:
Message: Insufficient system resources exist to complete the requested service.
Stack trace: at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.ReadCore(Byte buffer, Int32 offset, Int32 count)
at System.IO.FileStream.Read(Byte array, Int32 offset, Int32 count)
at GOGCompanionApp.Worker.DownloadChunk(Object downloadObject)
one InvalidOperationException after the login and one IOException after the download is finished.
To workaround this problem I have to backup (or manually download) the file, remove the entry in the list.
If the file is present the Downloader just skips it without errors (no verification, because no MD5). But as soon as the Downloader is actually downloading the file the problem happens again (tried it several times).