Sure, you can find the tool here,
@John Ievers:
mbMapInfoRasterTool on GithubThe feature you are mentioning lets you select a folder with sub folders.
The tool creates a new MRR for all the ASC files in each sub folder. You should end up with as many MRR as you have sub folder, if they all hold ASC files.
It will also create TAB files for all the ASC files using the coordinate system that you select. If TAB files already exists, they will get overwritten.
Don't use it in anger as I haven't tested it with thousands of files :-)
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Peter Horsbøll Møller
Pitney Bowes
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