feedback from migrating a project

hack/migrate.md

@@ -11,11 +11,14 @@ Options:
 
 ## Migrating projects using this library
 
-The migration was done creating a migration script `migration.mig`. It can be used
+The migration was done creating a migration script `migrate.mig`. It can be used
 to migrate packages or whole projects using this library to the new package structure and module name.
 It is executed by using the same migration Bash script `migrate.sh` using the option
 
 `--script <migration script>` migrate a project using the OCM library.
 
-Optionally, package paths can be added as additional arguments to the command line. By default, the
-complete current working directory is migrated.
+Optionally, package paths can be added as additional arguments to the command line. Note that by default, if package paths
+are not specified, the complete current working directory is migrated, which might include `.git`, `.vscode` 
+or any other subfolders you have there.
+
+If you want to run the script on `macOS`, make sure you are using it with `GNU sed`.