It would be great to be able to right-click on a folder with changes and start a review from there.
you should be able to do that pretty easily using scripting.
something like
ccollab admin review create --creator timmy --title "test cmdline creation" --custom-field "Overview=testoverview" --custom-field "defect=123456" --deadline '2015-12-12' --display-changelists-as "district" --group "a5afe6af13d2b5224f36b80cda29ba7f" --template "Custom Template" --restrict-access "anyone"
ccollab addchanges last .
This should generate a new review with specified info, then add all the changed files in the current folder and subfolders to the last review (if your new review was the last one to be generated), otherwise just look up the options for addchanges.
guess the tricky bits are the defined data (if you want to pre-fill them) otherwise you can leave them to be filled in once the review has been generated.
you can add the above text in a bat file and either set it in your send to folder, or set up the registry to run it off a new rightclick menu option.
In any case, it's a pretty simple change which would be welcomed oficially, but for the moment a workaround exists.