@chrishamm Thank you, that did fix both problems.
Didn't work in first try, as when I created a macro file it had no extension and I tried calling it with '.g'.
Is it possible to force it into error state instead of just yielding a warning if the macro doesn't exist?
I went with the custom macro approach, as I guess the start.g macro would be called before the actual print file and then I would miss the option of setting temperature in the slicer.
I made a new directory prefixed with a dot and it had the expected effect of hidding it from the dashboard 🙂