Yes. If you upload a file from an online file storage service we are integrated with (eg. Dropbox, Box.net, Google Drive) and make changes to that file in the cloud service, the change will also appear in Wealthbox.
However, if you make a change to a file you have uploaded from your computer, the changes will not carry over to the file stored in Wealthbox Cloud. You will need to re-upload the file with the updates.