For other folks' SD carded files I do not try to put them on my 595, it never works. The 595 and sometimes Base Camp seem to have a problem moving files directly from an SD card. What I do, because the laptop doesn't care what the card format is:
I have a Document folder on my laptop named Base Camp Routes and Points. I copy the route from the SD card to that folder, making sure I note the route name. I then make sure Garmin Express is shut down completely. You may have to go to the menu all the way at the bottom right of your computer to see if it's running in the background. If it is, right click and Quit. Trust me, Express and Base Camp do not play well together.
EDIT: from here on it's helpful to make a side trip into Garmin Express. This will help in the future, believe me. Open Garmin Express. be patient, it takes a while. When it's running, in Settings, untick the "start automatically when device is connected" and the "run in background" boxes. Save, then close Garmin Express. And check the computer bottom right menu again, close Express again if running in the background.
I then open Base Camp and wait. It takes a while for Garmin software to boot up. Just wait or do laundry or brush the dog's teeth or whatever. Give it plenty of time. Do not connect your 595 yet. I then pick the Base Camp list folder I want to import to, then select File/Import Into
[folder name], then the usual file search to select the route to import then OPEN. Now I have the route in a List Folder in Base Camp and can do with it as I wish including transferring to my device.
For internal memory clearing, pg 2 of this thread ->
https://www.zumouserforums.co.uk/viewto ... 5&start=10 helped me immensely. But there's some things you need to do first:
1) transfer from your 595 any info (routes, Saved Points, tracks, etc.) that you want to save to Base Camp;
2) ON YOUR 595, not plugged into Base Camp, delete any active routes you do not want in memory any more;
3) ON YOUR 595, not plugged into Base Camp, delete any active Saved Points you do not want in memory any more;
4) follow the directions from dave726 on pg 2 in the thread link above.
Now you will have as much free memory as you can get. To prevent this from happening again I do this:
From Base Camp, I do NOT put routes in internal memory. This eats up memory and the way to get it back is to delete the route. But I don't want many routes deleted. I want them always available. But I don't want to fill up memory. See the dilemma? The way around this is to NOT transfer routes to Internal Storage from Base Camp. I drag and drop my routes to User Memory, i.e., my installed SD Card in the 595. This way you can delete an active route and never have to transfer it from Base Camp again. Deleting it from Internal Storage ON THE DEVICE does not delete it from User Memory so it can easily be re-imported ON THE DEVICE whenever you want to and it's not filling internal memory by being active all the time. File (route) management for Internal and User Storage can be done in Base Camp without removing the SD card from the device as long as active routes are deleted first as described above.