The Insert Stuff button can be used anywhere there’s a text input area to submit embedded videos. Combined with Mediasite, this is ideal for submitting videos larger than 2GB that have been recorded previously.
Step 1) For Discussions or Assignments with text submission, start by clicking Insert Stuff
Step 2) Choose Mediasite
Step 3) Choose Upload
Step 4) Choose Upload Video
Step 5) Choose your file
Step 6) Add a title and (optional) description. Click Create Presentation
Step 7) Wait for the file upload. You will need to stay on this screen until the upload completes, this may take several minutes. 
Step 8) Once your file is uploaded, you will see the "Success" message. At this point you can continue, while Mediasite works in the background. You don't need to stay on the page. 
Step 9) At this point (while the "Currently Working" message is displayed) continue with adding your video by clicking "Add Presentation to Brightspace" and choose "Player Only" or "Abstract + Player"
Step 10) You may be prompted to make the video visible, click "OK".
Step 11) Back in BOLT, you can "Insert" the video.
Step 12) Submit your Assignment or Discussion with the video.
Please note: your video may not be fully finished processing when you submit. That is OK. The full video will become visible but may take several minutes.