Is the word 'BEGIN' actually in your macro? It shouldn't be.
Try opening a file and manually running the macro to see if it works.
Also, the call I believe should be to the macro name, not the file. All macros in the 'Macros' folder get loaded into memory. You then reference them through the name. It is easily possible for a single file to contain multiple macros so calling it at that level does not work.
In regards to errors, I have a vague recollection that calling IsoDraw via this method suppresses errors since it has traditionally been used in batches or through automation where an error pop-up would cause a potential lock.