Name the .gif bdWhateverNameYouWant.gif. You need to make a file called BoardMetadata.xml. I don't know if there is a template or not. I grab one out of an existing map. Remove the stuff that doesn't apply and change the stuff that does, but leave the xml structure the same. There are comments in existing maps, so you should be able to figure out most of what you need to put in. I think you also have to include a file named "data". As I understand it this is no longer used but vasl might be confused if it isn't found. I add it just in case, again changing the values to match the map. Take all three files (the .gif, BoardMetadata.xml and data) and add them to a .zip archive named bdWhateverNameYouWant.zip, then get rid of the .zip extension.
That is a good and very complete explanation. Although it says that there are four additional files (beyond the .gif and the two I listed), “colors”, “colorSSR”, “overlaySSR”, and “SSRControls”, those are not necessary, as far as I can tell, if you are creating a bare-bones vasl map to use, for example, for proof-of-concept or playtesting.
