As discussed in the BASIC Facebook group, I was unable to get the extension to work on my Mac with hdfmonkey v0.3, even though that version works fine on the command line. I was just getting a popup with the error "Command 'NextBASIC: Run with cspect' resulted in an error".

With a bit of extension debugging, I eventually figured out it's the command at auto-run.task.js:105 that was throwing the error. In my particular case, that was expanding to:

hdfmonkey put "/Applications/_Non-Apple/Games/SpecNext/Emulators/2gb/cspect-next-2gb.img" "/Users/calum/.vscode/extensions/remysharp.nextbasic-1.11.12/autoexec-pre-compiled.bas" /nextzxos/autoexec.bas

although I didn't dig deep enough to find out exactly why this was failing with v0.3. (As I said, it worked fine on the command line.) Knowing that v0.4 was required would have saved me a bit of time and bother, and might save someone else the same in future 😊