Hey deerderf,
We understand you're getting an error when attempting to move file to your flash drive and have tried zipping the file with the issue persisting. We'll be happy to help.
There could be several different reasons for this error to appear. First, make sure the file name doesn't have any invalid characters. If there's any special characters, remove them and try again.
Also, if the file hasn't completely downloaded, or is incomplete or damaged, you may need to try redownloading the file and then try the transfer again.
Let's, also make sure that you don't have the file open on your Mac while attempting to transfer it.
Lastly, if you continue to have issues when transferring files to this particular drive with multiples files, you may also need to try repairing the drive using Disk Utility:
Repair a storage device in Disk Utility on Mac
We hope this information helps out! Keep us posted on the results.
Take care.