ThumbsPlus can create thumbnails for CDR, PAT and BMF files; however, it can only extract the preview bitmap from them. There is no internal support for the proprietary Corel format.
If you have Corel, you can set up CDR and PAT files for external OLE support (using the File Type Configuration dialog box), which will allow you to create much nicer thumbnails for them. However, the price is high: Corel is a very slow OLE server, so it takes much longer to create the thumbnails.
Corel files may also be viewed, printed, or copied to the clipboard as metafiles using the OLE support.
CorelGALLERY files (.BMF) can be viewed and thumbnailed via OLE also, as long as the Corel Gallery program itself is installed. As with the CDR files, OLE is considerably slower than the internal bitmap support.