My Cloud EX2 Ultra , error when uploading folders

I just got myself the EX2 Ultra and did the install. Now I uploaded some folders with my pictures, but:
-It takes like 10-15 seconds to upload one picture (got 20 mb download), cant i connect my pc directly to the cloud device (for example usb?)
-i tried to download it now over night because it took so long, and this morning it showed that it uploaded only 1200 pictures of 14k.The reasons were either server timeout or file not loaded.
I cant explain myself why it worked with some of them?
Thanks for help :slight_smile: