Run VideoDoc on your Mac.
Apple blocks apps that are not registered with them, and that registration costs $99 a year. VideoDoc is a small independent tool, so instead you do a one-time 10 second unlock. Here it is, with a copy button. You need an Apple Silicon Mac (M1 or newer).
Unzip the download
Download the zip from your Gumroad receipt and double-click it to unzip. You get a folder with VideoDoc inside. You can leave it wherever you like, you do not need to move it.
Open Terminal
Press Cmd+Space, type Terminal, press Return. A small text window opens. That is all you need it for.
Paste one line, press Return
If your download went to your Downloads folder (most do) and you did not rename it, copy this whole line, paste it into Terminal, and press Return. VideoDoc unblocks and opens by itself.
xattr -dr com.apple.quarantine ~/Downloads/VideoDoc_*_macOS/VideoDoc.app && open ~/Downloads/VideoDoc_*_macOS/VideoDoc.app
From now on, just double-click VideoDoc. No Terminal ever again. The first run downloads the speech engine once (up to ~500 MB); after that your own files work fully offline.
Got "no matches found" or "No such file"? Then VideoDoc is not in your Downloads folder. Type xattr -dr com.apple.quarantine and a space, then drag VideoDoc from Finder onto the Terminal window (drag it BEFORE you press Return), press Return, and double-click VideoDoc.
Why this step, honestly
When you download any app, your Mac marks it as "from the internet" and only lets it run if the maker pays Apple $99 every year for a registration. VideoDoc has not paid that yet, so without this step your Mac shows a scary message that the app "is damaged." It is not damaged. That is just Apple's standard wording for unregistered apps.
The line you paste removes that internet mark from this one app only. It does not touch your Mac's protection, and please never turn that protection off for VideoDoc or any other app. If VideoDoc earns enough, I will pay Apple's registration and this page will be deleted, because the app will simply open.
Something not working? Reply to your Gumroad receipt with a screenshot and I will make it right.