I have a similar issue with my computer freezing, though I have not resized the drive.
Windows 7, 64 bit, stablebit cloud drive version 1.0.0.283. 16GB RAM and 8core intel cpu. Using amazon clouddrive as the target.
Have tried it with default worker / maintance process and with increments of 100 up to 1000. Have default cache size and all the way up to 10GB of cache, on a local SSD.
Files are being copied from a 7200 RPM sata HD. Cloud drive size doesn't seem to matter, 10GB, 50GB, 1TB, 5TB, 10TB.
Have 950mbit download, 650mbit download capabilities.
Encryption is enabled, default settings.
Process to recreate, and have done this on two different computers:
Create cloud drive
Copy 900MB video file
Successfully uploads and can retreive fine
Create cloud drive
Copy >10 x 900MB video file
Can see in Amazon web gui that it starts uploading the files
Windows explorer crashes and and does not recover (Ctrl-alt-del and starting explorer.exe does not recover it)
Non-microsoft applications freeze, IE firefox and stablebit cloud drive, showing "Not Responding" over the window.
Wait 15-30 minutes and it does not recover
Hard reset computer
Stablebit recovers the drive fine, shows data in the "to be uploaded" but it does not continue (if add new data it will upload the new data but not the old copy data before hard reset)
Have this problem on any data larger than about 6GB if it is more than 1 file.
Have uninstall/reinstall stablebit and performed reboots between those actions.
Tried it with creating a new stablebit clouddrive as well.
Only have amazon clouddrive to test.