Do you have on root of internal or external SD folder Garmin or you add in folder Android/data/....
If you have in folder Android/.... then try turn off/on your device and see if then all work.
I have one time problem when i uninstall SP over phone and if i look over phone no SP folder visible but when i connect device to Pc i see that folder is still there.
So i manualy delete all folder of SP and turn device off/on, add folder Garmin on device and install apk, turn device off/on and then run SP and all work.
On some device folder Map or only .img is set ass read only after you copy from Pc to device, don't know why.