iMovie saves your work automatically as you go. To finish your video:
Taken together, "iMovie 1025 dmg" most plausibly describes a macOS disk-image installer for a particular iMovie build (e.g., an installer file named something like iMovie_10.2.5.dmg or iMovie_1025.dmg). Below are details covering context, usage, installation, verification, troubleshooting, and safety. imovie 1025 dmg
Ability to import projects started on an iPhone or iPad (version 2.3) to finish on your Mac. How to Safely Get iMovie 10.2.5 iMovie saves your work automatically as you go