Another option is to try imagemagick convert utility,Imagemagic can be easily installed using software center or synaptic.
Since the document is scanned it should be a bitmap which imagemagick can handle, only the version of the .cdr would be a concern, you did not mention the version of the cdr file so you may just try imagemagick, at your terminal in the directory where the .cdr file is located, run the convert utility like this;
convert image.cdr image.png
this will convert the .cdr image called image.cdr to a .png image called image.png file that you can easily use, probably vectorize by tracing in inkscape if you wish.
See the imagemagic documentation on the convert utility if more control over the output is needed. hope the output is satisfactory.