If you move your home folder to a drive other than the boot drive, then make sure you have an account which still has its home folder on the boot drive. Otherwise, if the HDD fails, you will be unable to start the Mac even if the boot drive (SSD) is perfectly OK.
Click Change, then select a new location for your files. From now on, new songs and other items you import are stored in the new location. Songs you’ve already imported stay in their current location. To go back to storing imported files in the default folder, choose Music. In the Change folder window, select a folder that you want to change to, and click the Select Folder button. Change the save destination for the ScanSnap Home folder in ScanSnap Home. The ScanSnap Home folder is displayed under the Mac folder in the folder list view on the main window. For example if you want to change the install location to a folder on an external drive the line should look something like this: Of course you must change EXTERNAL DRIVE and FOLDER NAME to the actual drive and folder name on your Mac.
Also, since most documents in the 'Documents' folder are quite small, there is maybe some benefit in keeping most of them on the SSD.
I have two documents folders, one on SSD one on HDD. The default is on SSD. I figure that recently saved ones will be likely to be re-accessed soon, and I'd like good performance. I move old files to the HDD.
Mac Os Applications Folder
Both Documents folders are in the Finder Sidebar, so it's easy to override the default choice.
Mac Download File Location
The <blahs> appear to be some hash of either the computer or the software being downloaded. Try the following:
Open a Terminal
sudo find /private -name ' SomePartOfTheDriverNameYouAreLookingFor' -print
then sudo cd <the directory shown above>
Note I don't see /private in finder because of the permissions on it (hence the need for sudo above).
Also note, I had one directory in <blah> named -Cache- which is tricky to cd into because the leading - is perceived as an argument to cd, so I just cd into the entire directory path instead.
Finally, be wary doing things as root (sudo) as you can end up damaging your OS (so don't go around removing files you are not sure about)