Can't add audio, or video!

Okay, so I found this program on TechRadar since Windows Movie Maker vanished in Windows 10. i’m grateful that it hasn’t crashed… I have been able to add some videos but here are my problems:

1- I have 3 video tracks, if I try to add another video track it lets me, but will not let me drag the video on it, it has a circle crossed out.
2-I add an M4A file, it plays. I add the audio track which shows on the timeline. I try to drag it there, I get the circle crossed out again! I add mp3, same problem.
3-It seems like I have to add the file multiple times - I may want to do several cuts in the same file, but I can’t find anywhere where it keeps the import …instead I have to add the file again.

Save/Close/Re-Open.
or use the file menu to import.

This is a known bug which has been reported many times to the devs.

First add/import your files to the Playlist (aka: Media bin)

You can still find it for installing into Windows 10 - I have it and it works fine in W10 Pro 64bit.
See http://codecpack.co/download/Windows-Live-Movie-Maker.html

what about the audio with the red crossed out circle?

Save/Close/Re-Open.
or use the file menu to import.

Thasnk u so much, u just saved me for my school project