diff --git a/aegisub/auto4_lua.cpp b/aegisub/auto4_lua.cpp
index 5e422401e..68c04d11a 100644
--- a/aegisub/auto4_lua.cpp
+++ b/aegisub/auto4_lua.cpp
@@ -55,7 +55,8 @@ namespace Automation4 {
 
 	// LuaStackcheck
 
-#ifdef _DEBUG
+//#ifdef _DEBUG
+#if 0
 	struct LuaStackcheck {
 		lua_State *L;
 		int startstack;
@@ -241,7 +242,7 @@ namespace Automation4 {
 
 			// load user script
 			LuaScriptReader script_reader(GetFilename());
-			if (lua_load(L, script_reader.reader_func, &script_reader, GetFilename().mb_str(wxConvUTF8))) {
+			if (lua_load(L, script_reader.reader_func, &script_reader, GetPrettyFilename().mb_str(wxConvUTF8))) {
 				wxString *err = new wxString(lua_tostring(L, -1), wxConvUTF8);
 				err->Prepend(_T("Error loading Lua script \"") + GetPrettyFilename() + _T("\":\n\n"));
 				throw err->c_str();
@@ -412,7 +413,7 @@ namespace Automation4 {
 		}
 
 		LuaScriptReader script_reader(fname.GetFullPath());
-		if (lua_load(L, script_reader.reader_func, &script_reader, s->GetFilename().mb_str(wxConvUTF8))) {
+		if (lua_load(L, script_reader.reader_func, &script_reader, fname.GetFullName().mb_str(wxConvUTF8))) {
 			lua_pushfstring(L, "Error loading Lua include \"%s\":\n\n%s", fname.GetFullPath().mb_str(wxConvUTF8).data(), lua_tostring(L, -1));
 			lua_error(L);
 			return 0;
@@ -475,6 +476,15 @@ namespace Automation4 {
 		lua_getfield(L, LUA_REGISTRYINDEX, "progress_sink");
 		if (lua_isuserdata(L, -1)) {
 			LuaProgressSink *ps = LuaProgressSink::GetObjPointer(L, -1);
+
+			if (result) {
+				// if the call failed, log the error here
+				wxString errmsg(lua_tostring(L, -2), wxConvUTF8);
+				ps->AddDebugOutput(_T("\n\nLua reported a runtime error:\n"));
+				ps->AddDebugOutput(errmsg);
+				lua_pop(L, 1);
+			}
+
 			// don't bother protecting this with a mutex, it should be safe enough like this
 			ps->script_finished = true;
 			// tell wx to run its idle-events now, just to make the progress window notice earlier that we're done
@@ -628,7 +638,7 @@ namespace Automation4 {
 
 		ps->ShowModal();
 		wxThread::ExitCode code = call.Wait();
-		if (code) ThrowError();
+		//if (code) ThrowError();
 
 		delete ps;
 	}
@@ -676,6 +686,7 @@ namespace Automation4 {
 	void LuaFeatureFilter::ProcessSubs(AssFile *subs, wxWindow *export_dialog)
 	{
 		GetFeatureFunction(1); // 1 = processing function
+		assert(lua_isfunction(L, -1));
 
 		// prepare function call
 		// subtitles (undo doesn't make sense in exported subs, in fact it'll totally break the undo system)
@@ -685,6 +696,9 @@ namespace Automation4 {
 		if (has_config && config_dialog) {
 			assert(config_dialog->LuaReadBack(L) == 1);
 			// TODO, write back stored options here
+		} else {
+			// no config so put an empty table instead
+			lua_newtable(L);
 		}
 
 		LuaProgressSink *ps = new LuaProgressSink(L, export_dialog, false);
@@ -695,7 +709,7 @@ namespace Automation4 {
 
 		ps->ShowModal();
 		wxThread::ExitCode code = call.Wait();
-		if (code) ThrowError();
+		//if (code) ThrowError();
 
 		delete ps;
 	}
@@ -722,12 +736,16 @@ namespace Automation4 {
 
 		ps->ShowModal();
 		wxThread::ExitCode code = call.Wait();
-		if (code) ThrowError();
+		//if (code) ThrowError();
 
 		delete ps;
 
 		// The config dialog table should now be on stack
-		return config_dialog = new LuaConfigDialog(L, false);
+		if (!code) {
+			return config_dialog = new LuaConfigDialog(L, false);
+		} else {
+			return config_dialog = 0;
+		}
 	}
 
 
diff --git a/aegisub/base_grid.cpp b/aegisub/base_grid.cpp
index b4dea94f4..9aac317a2 100644
--- a/aegisub/base_grid.cpp
+++ b/aegisub/base_grid.cpp
@@ -865,7 +865,9 @@ void BaseGrid::SetColumnWidths() {
 // Gets dialogue from map
 AssDialogue *BaseGrid::GetDialogue(int n) {
 	try {
-		return AssEntry::GetAsDialogue(*(diagMap.at(n)));
+		AssEntry *e = *diagMap.at(n);
+		if (e->GetType() != ENTRY_DIALOGUE) return NULL;
+		return AssEntry::GetAsDialogue(e);
 	}
 	catch (...) {
 		return NULL;
diff --git a/aegisub/frame_main_events.cpp b/aegisub/frame_main_events.cpp
index 5ce99903e..37842d31a 100644
--- a/aegisub/frame_main_events.cpp
+++ b/aegisub/frame_main_events.cpp
@@ -998,11 +998,13 @@ void FrameMain::OnOpenAutomation (wxCommandEvent &event) {
 ///////////////////////////////////////////////////////////
 // General handler for all Automation-generated menu items
 void FrameMain::OnAutomationMacro (wxCommandEvent &event) {
+	// Clear all maps from the subs grid before running the macro
+	// The stuff done by the macro might invalidate some of the iterators held by the grid, which will cause great crashing
+	SubsBox->Clear();
+	// Run the macro...
 	activeMacroItems[event.GetId()-Menu_Automation_Macro]->Process(SubsBox->ass, SubsBox->GetAbsoluteSelection(), SubsBox->GetFirstSelRow(), this);
-	// check if modifications were made and put on undo stack
-	AssFile::Popping = true; // HACK to avoid getting an additional undo point on stack
-	SubsBox->LoadFromAss(AssFile::top, true, true);
-	AssFile::Popping = false;
+	// Have the grid update its maps, this properly refreshes it to reflect the changed subs
+	SubsBox->UpdateMaps();
 }
 
 
diff --git a/automation/include/karaskel.lua b/automation/include/karaskel.lua
index e7412d14c..55f3267b6 100644
--- a/automation/include/karaskel.lua
+++ b/automation/include/karaskel.lua
@@ -52,7 +52,7 @@ function karaskel.collect_head(subs)
 		local l = subs[i]
 		if l.class == "style" then
 			styles.n = styles.n + 1
-			styles[n] = l
+			styles[styles.n] = l
 			styles[l.name] = l			
 		elseif l.class == "info" then
 			local k = l.key:lower()
@@ -91,23 +91,23 @@ end
 -- Modifies the line parameter
 function karaskel.preproc_line(subs, meta, styles, line)
 	-- Assume line is class=dialogue
-	local kara = aegisub.parse_karaoke_data(line.text)
+	local kara = aegisub.parse_karaoke_data(line)
 	line.kara = { n = 0 }
 	line.furi = { n = 0 }
 	
 	if styles[line.style] then
-		line.style = styles[line.style]
+		line.styleref = styles[line.style]
 	else
-		aegisub.debug.out("WARNING: Style not found: " .. line.style .. "\n")
-		line.style = styles[1]
+		aegisub.debug.out(2, "WARNING: Style not found: " .. line.style .. "\n")
+		line.styleref = styles[1]
 	end
 	
 	line.text_stripped = ""
 	
 	local curx = 0
 	local worksyl = { }
-	for i = 0, #line.kara do
-		local syl = line.kara[i]
+	for i = 0, #kara do
+		local syl = kara[i]
 		
 		-- Spaces at the start and end of the syllable are best ignored
 		local prespace, syltext, postspace = syl.text_stripped:match("^([ \t]*)(.-)([ \t]*)$")
@@ -155,7 +155,7 @@ function karaskel.preproc_line(subs, meta, styles, line)
 		-- If this is the start of a highlight group, do regular processing
 		if prefix ~= "#" and prefix ~= "＃" then
 			-- Update stripped line-text
-			line.text_stripped = line.text_stripped + syl.text_stripped
+			line.text_stripped = line.text_stripped .. syl.text_stripped
 			
 			-- Copy data from syl to worksyl
 			worksyl.text = syl.text
@@ -165,16 +165,16 @@ function karaskel.preproc_line(subs, meta, styles, line)
 			worksyl.end_time = syl.end_time
 			worksyl.tag = syl.tag
 			worksyl.line = line
-			worksyl.style = line.style
+			worksyl.style = line.styleref
 			
 			-- And add new data to worksyl
 			worksyl.text_stripped = syltext
-			worksyl.width = aegisub.text_extents(line.style, syltext)
-			curx = curx + aegisub.text_extents(line.style, prespace)
+			worksyl.width = aegisub.text_extents(line.styleref, syltext)
+			curx = curx + aegisub.text_extents(line.styleref, prespace)
 			worksyl.left = curx
 			worksyl.center = curx + worksyl.width/2
 			worksyl.right = curx + worksyl.width
-			curx = curx + worksyl.width + aegisub.text_extents(line.style, postspace)
+			curx = curx + worksyl.width + aegisub.text_extents(line.styleref, postspace)
 			
 			-- TODO: inlinefx here
 		end
@@ -192,10 +192,12 @@ function karaskel.preproc_line(subs, meta, styles, line)
 	line.kara[line.kara.n] = worksyl
 	
 	-- Full line sizes
-	line.width, line.height, line.descent, line.extlead = aegisub.text_extents(line.style, line.text_stripped)
+	line.width, line.height, line.descent, line.extlead = aegisub.text_extents(line.styleref, line.text_stripped)
+	-- And positioning (FIXME: assume centering for now)
+	line.left = (meta.res_x - line.styleref.margin_l - line.styleref.margin_r - line.width) / 2 + line.styleref.margin_l
 	
 	-- Generate furigana style
-	local furistyle = table.copy(line.style)
+	local furistyle = table.copy(line.styleref)
 	furistyle.fontsize = furistyle.fontsize / 2
 	furistyle.outline = furistyle.outline / 2
 	
diff --git a/automation/include/unicode.lua b/automation/include/unicode.lua
index e278214f1..2f9ce952d 100644
--- a/automation/include/unicode.lua
+++ b/automation/include/unicode.lua
@@ -35,7 +35,12 @@ module("unicode")
 -- Return the number of bytes occupied by the character starting at the i'th byte in s
 function charwidth(s, i)
 	local b = s:byte(i)
-	if b < 128 then
+	if not b then
+		--aegisub.debug.out(3, "unicode.charwidth of '%s' @ %d, nil byte\n", s, i)
+		-- FIXME, something in karaskel results in this case, shouldn't happen
+		-- What would "proper" behaviour be? Zero? Or just explode?
+		return 1
+	elseif b < 128 then
 		return 1
 	elseif b < 224 then
 		return 2
diff --git a/automation/include/utils.lua b/automation/include/utils.lua
index 0656ee731..fc798c223 100644
--- a/automation/include/utils.lua
+++ b/automation/include/utils.lua
@@ -143,3 +143,14 @@ function string.headtail(s)
 		return s, ""
 	end
 end
+
+-- Clamp a number value to a range
+function clamp(val, min, max)
+	if val < min then
+		return min
+	elseif val > max then
+		return max
+	else
+		return val
+	end
+end