Hello,
I keep getting the error in the screenshot when trying to import MEG/EEG data. 
I reinstalled brainstorm multiple times and it still doesn't work. I'm running Windows 10 on my computer, if that helps.
EDIT: The bug has been resolved by getting somebody with a working brainstorm to import the .mat file and give me the protocol in a .zip
What is this Fieldtrip.mat file and what is it doing in the brainstorm database folder?
You should not be copying or moving files manually in this brainstorm_db folder:
https://neuroimage.usc.edu/brainstorm/Tutorials/CreateProtocol#Brainstorm_folders
If you want to learn how to use Brainstorm, please start by following all the introduction tutorials (section "Get started") at least until #19 using the tutorial dataset, before trying to process your own recordings.
https://neuroimage.usc.edu/brainstorm/Tutorials
Then for importing data, make sure you select the correct file format in the import window.