From 8a1592d4b61b350f50bb6c8bb92e36dbbaa66b84 Mon Sep 17 00:00:00 2001
From: Thomas Weber <thomas.weber@notengrafik.com>
Date: Mon, 15 Jun 2020 11:23:16 +0200
Subject: [PATCH 1/2] Make sure we have an active score

---
 src/Run.mss | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/Run.mss b/src/Run.mss
index dca4374..737175e 100644
--- a/src/Run.mss
+++ b/src/Run.mss
@@ -45,13 +45,18 @@ function DoExport (filename) {
     Self._property:libmei = libmei4;
     libmei.destroy();
 
-    // Deal with the Progress GUI
     // set the active score here so we can refer to it throughout the plugin
     Self._property:ActiveScore = Sibelius.ActiveScore;
+    if (Self._property:ActiveScore = null)
+    {
+        Sibelius.MessageBox('No score to convert. Can not export to ' & filename);
+        return false;
+    }
 
     // Set up the warnings tracker
     Self._property:warnings = CreateSparseArray();
 
+    // Deal with the Progress GUI
     progCount = Sibelius.ActiveScore.SystemStaff.BarCount;
     fn = utils.ExtractFileName(filename);
     progressTitle = utils.Format(_InitialProgressTitle, fn);

From eafbdff722565d7d9f6bc0f533b371869d66483c Mon Sep 17 00:00:00 2001
From: Thomas Weber <thomas.weber@notengrafik.com>
Date: Mon, 15 Jun 2020 20:18:55 +0200
Subject: [PATCH 2/2] Message when no active score was found

---
 src/Run.mss | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Run.mss b/src/Run.mss
index 737175e..24e9643 100644
--- a/src/Run.mss
+++ b/src/Run.mss
@@ -49,7 +49,7 @@ function DoExport (filename) {
     Self._property:ActiveScore = Sibelius.ActiveScore;
     if (Self._property:ActiveScore = null)
     {
-        Sibelius.MessageBox('No score to convert. Can not export to ' & filename);
+        Sibelius.MessageBox('Could not find an active score. Cannot export to ' & filename);
         return false;
     }