I often find that users are absolutely baffled about how to have a bitmap (this does not mean BMP file format) with transparency. In short, you don’t want a white box. The first thing to do is banish the JPG file format as it is a large part of the problem.
JPG does not support transparency. End of story. For those who wish to debate this, Adobe does have a proprietary variation of JPG that does support transparency. The key word is proprietary and it isn’t widely supported or used.
Once any bitmap is imported into CorelDRAW, it is no longer whatever native format you imported. So a JPG imported into CorelDRAW is no longer a JPG. Yea, good riddance! It also won’t improve the quality if the original JPG was full of compression artifacts. It just won’t get any worse.
Importing a bitmap that has transparency (PNG, TIF, CPT, PSD) into CorelDRAW, does not add a white background. Never! That doesn’t mean there isn’t a transparent object/layer (CPT or PSD) on top of a rectangular white shape. If the white shape exists in the file, importing the bitmap will bring in a group of objects including the white box. You can ungroup and delete the white object.
To me, the process of importing a bitmap into CorelDRAW first and then clicking Edit Bitmap process to delete the background is completely backwards. Instead, open the bitmap in Corel PHOTO-PAINT (or Photoshop if you choose). Get the transparency you desire and save to a format that supports transparency. Again, not the evil JPG! I typically use PNG or CPT. Photoshop users could use PSD as well. Import this file into CorelDRAW and you’ll get transparency. The added benefit is that you can easily import the bitmap with transparency into other files because it isn’t embedded inside of a CorelDRAW file. I often use the same transparent file to import into CorelDRAW, place inside InDesign, import into Microsoft Office applications or use on a Web site. There is a lot of flexibility if you follow this process!