After you've downloaded the m4vgear, then launch it, you'll see the main interface like the screenshot below and you'll know the conversion steps clearly. Open the menu button beside the button of minimize, then you'll see the list including language, help, register, order now, locate log file, check update about. So go to menu button to register(if you still have the trial version, you can click buy now to buy first).
When you launch M4VGear, you'll see the picture below ( iTunes can automatically be opened).Click "Add" button or "Add Files" icon, or drag your m4v files to the program.
After you have done the step one to click "Add", you'll see the following picture,then please follow the steps in the picture:
After you've added files sucessfully, then click the "Convert" button to start the coversion. Also, you can stop converting during the conversion by clicking Stop button. Besides, you can set the audio track by clicking the "wheel gear" icon on the end of each file list. What's more,if you don't want to put the converted files in the default folder, you can choose other output paths on the left bottom of the interface before your conversion.
Tips: Before the status show converting progress, please don't do anything with iTunes during converting, conversion may failed by occurring an error. Besides, when you have finished the conversion, you can find your converted files in the "History", you can click the History button on the right top.