When I get an attachment and it's a Microsoft file, I still just get the options for Preview, Edit in Browser, Edit in Word desktop app, and Save to OneDrive - BUT if I select Edit in Browser or in Edit in Word desktop app, and go to the Files tab, there's an option to Save As and I can then navigate on my computer to save it wherever I want. Yay!
Note that this only applies to Microsoft files. If I open a document with an attached .PDF, I get options to Preview and Save to OneDrive. If I select Save to OneDrive, it saves it SOMEWHERE but I can't tell it where I want it - BUT, after that, if I click on the attached file again and select View in OneDrive, the file opens in my browser and then I get an option to Download and I can save it wherever I like. If I select Preview at first, I can see the content and then I can select Save to OneDrive. Then, at the top of the Preview window, I get a chance to View in OneDrive. When I select that, the PDF opens in my browser and again, there's an option at the top of the window to Download. I can navigate and download it wherever I want.
Image files don't work as well - I tried a .jpg and a .png since I use those files a lot. I can select the attachment and get options to Preview or Save to OneDrive. If I select Save to OneDrive, it saves SOMEWHERE, but I can't choose where. When I click on the attachment in email again, I can View in OneDrive and then right-click-save to save it wherever I want. If I select Preview, it opens and gives me an option at the top of the screen to View in OneDrive. The file opens in the browser, and I can right-click-save and save it wherever I want.
I would REALLY like to be able to download these documents in one step by select them in the email and then click Download, or to drag and drop them into place. This is SO MANY EXTRA STEPS to do things I do in "old Outlook" in one step!!! It takes a lot more time between getting an email attachment and actually being able to DO MY JOB and edit these files.
As for the people at Microsoft actually working on this program, I'm sure they would LIKE to make this easier (the code must surely still be there from the old version!). They must be even more frustrated than we are!!! Here's hoping the bosses let them go ahead and fix this absolute MESS.