To edit an instant video and convert from MP4 to RMVB file in Corel VideoStudio Pro X5, follow these steps:
- Import your MP4 video into the software.
- Drag and drop the video onto the timeline.
- Edit the video as desired.
- Go to the "Export" tab and choose "Video File" as the output format.
- Select the RMVB format from the drop-down menu.
- Click on "Export" to save the edited video as a RMVB file.