What an awesome game!
Had a lot of fun!
I actually played all levels twice, as I didn't record the first run and did another with recording once I noticed your game description. Hope I am first XD
The hardest level is actually the 3rd one. I barely made it on my recorded run. I was much better in my first run on this level loosing only one unit :/
Anyway I uploaded my recordings here as proof:
https://www.file-upload.net/download-13627105/rec04.mp4.html
https://www.file-upload.net/download-13627106/rec03.mp4.html
https://www.file-upload.net/download-13627104/rec02.mp4.html
https://www.file-upload.net/download-13627107/rec01.mp4.html