As far a I know this is not possible at this time. While I still think PureRaw is superior to Topaz on high ISO images, I just purchased the newest version of Photo AI for its sharpening of slightly blurry images and upscaling capabilities. I don’t know if this is new to this version, but it allows cropping. This allows for much smaller .dng files!
Since the .dng’s are basically demosaiced 16 bit Tiffs I don’t see why the original Raw file can’t be cropped on export. I’m now cropping loose on images where even at my maximum 700mm on full frame the subject is small.
PureRAW is a batch processor, designed for you to drop a whole batch of photos in and process them all with a minimum of fuss. If you want to crop, that’s a job for Lightroom or equivalent.
I don’t use it that way and I’m not sure how many people use it to run all their files. I only find it helpful on high ISO files and running everything would be both a waste of my time and a huge increase in storage. YMMV, but please don’t make people who use it differently from you wrong.
Thats how I use it, batch process a load of RAW images. But then I work on them in Photoshop. There are several things that DxO PureRaw does not have, such as white balance and exposure, these often need adjusting. I then work on layers. DxO PureRaw is good but only does a very limited part of the processing.
I only use it on certain images, ones I’m considering printing or some of the best images. There is free software, which can crop and reduce the file size. But file size is not usually an issue these days. You can buy 5TB HD for under £100.
DxO I find far superior to Topaz AI, which I’m trying now but so many problems with it, it is still at beta stage, imo.