diff --git a/draw.cpp b/draw.cpp
index 5c67548..c699a8f 100644
--- a/draw.cpp
+++ b/draw.cpp
@@ -405,14 +405,17 @@ void GraphicsWindow::MouseLeftDown(double mx, double my) {
             SS.GetParam(hr.param(0))->val = 0;
             break;
 
-        case MNU_ARC:
+        case MNU_ARC: {
             if(!SS.GW.LockedInWorkplane()) {
                 Error("Can't draw arc in 3d; select a workplane first.");
                 ClearPending();
                 break;
             }
             hr = AddRequest(Request::ARC_OF_CIRCLE);
-            SS.GetEntity(hr.entity(1))->PointForceTo(v);
+            // This fudge factor stops us from immediately failing to solve
+            // because of the arc's implicit (equal radius) tangent.
+            Vector adj = SS.GW.projRight.WithMagnitude(2/SS.GW.scale);
+            SS.GetEntity(hr.entity(1))->PointForceTo(v.Minus(adj));
             SS.GetEntity(hr.entity(2))->PointForceTo(v);
             SS.GetEntity(hr.entity(3))->PointForceTo(v);
             ConstrainPointByHovered(hr.entity(2));
@@ -423,7 +426,7 @@ void GraphicsWindow::MouseLeftDown(double mx, double my) {
             pending.point = hr.entity(3);
             pending.description = "click to place point";
             break;
-
+        }
         case MNU_CUBIC:
             hr = AddRequest(Request::CUBIC);
             SS.GetEntity(hr.entity(1))->PointForceTo(v);
diff --git a/polygon.h b/polygon.h
index 281bf23..b057e9f 100644
--- a/polygon.h
+++ b/polygon.h
@@ -221,9 +221,9 @@ public:
 
 class SKdTree {
 public:
-    static const int BY_X = 1;
-    static const int BY_Y = 2;
-    static const int BY_Z = 3;
+    static const int BY_X = 0;
+    static const int BY_Y = 1;
+    static const int BY_Z = 2;
     int which;
     double c;
 
diff --git a/win32/w32main.cpp b/win32/w32main.cpp
index 5ff0208..21344c6 100644
--- a/win32/w32main.cpp
+++ b/win32/w32main.cpp
@@ -923,8 +923,23 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
     // Create the heap that we use to store Exprs and other temp stuff.
     FreeAllTemporary();
 
+    // A filename may have been specified on the command line; if so, then
+    // strip any quotation marks, and make it absolute.
+    char file[MAX_PATH] = "";
+    if(strlen(lpCmdLine)+1 < MAX_PATH) {
+        char *s = lpCmdLine;
+        while(*s == ' ' || *s == '"') s++;
+        strcpy(file, s);
+        s = strrchr(file, '"');
+        if(s) *s = '\0';
+    }
+    char absoluteFile[MAX_PATH] = "";
+    if(*file != '\0') {
+        GetFullPathName(file, sizeof(absoluteFile), absoluteFile, NULL);
+    }
+    
     // Call in to the platform-independent code, and let them do their init
-    SS.Init(lpCmdLine);
+    SS.Init(absoluteFile);
 
     ShowWindow(TextWnd, SW_SHOWNOACTIVATE);
     ShowWindow(GraphicsWnd, SW_SHOW);