You have a valid point. I hadn't thought of that kind of usage, this is why giving me use cases here is important. As this makes so much sense I can put this in plus its quite trivial to do

So work flow would be:
1. When you start app and download first time, dialog defaults to your set default download folder.
2. You travel to another folder and DL item.
3. Dialog will remember last used folder.
Extra: You can set from settings to always use your defined default DL folder without showing dialog.

Oh, and I have multi selection for DL/UL in mind. I looked at it quickly and seems that PyQt4 QFileDialog.getOpenFileName() is not working as expected on maemo. Next step would be to start implementing the dialog myself, and that is something i don't want to spend time on at this point. For DL I would need to modify the tree view/model to support selecting items somehow. Maybe a long press and "select for download" would be something to consider.

Thanks for the feedback.

Edit. Done, classic 4 liner