diff --git a/application/editormode.cpp b/application/editormode.cpp
index 3eef9330..a3373e73 100644
--- a/application/editormode.cpp
+++ b/application/editormode.cpp
@@ -3934,7 +3934,8 @@ void editor_mode::render_edit_menu()
 		group_selection();
 	if (ImGui::IsItemHovered())
 		ImGui::SetTooltip("%s", STR_C("The selected models move together from now on; a click on one selects them all. Shift+LMB adds a model to the selection"));
-	if (ImGui::MenuItem(STR_C("Ungroup"), "Ctrl+Shift+G", false, selected && m_node->group() > 1))
+	// Delete above may have just dropped the node, selected is from before it
+	if (ImGui::MenuItem(STR_C("Ungroup"), "Ctrl+Shift+G", false, m_node != nullptr && m_node->group() > 1))
 		ungroup_selection();
 	if (ImGui::IsItemHovered())
 		ImGui::SetTooltip("%s", STR_C("The models of the group move each by itself again"));
diff --git a/application/editormodeinfra.cpp b/application/editormodeinfra.cpp
index 1e18d042..46585e96 100644
--- a/application/editormodeinfra.cpp
+++ b/application/editormodeinfra.cpp
@@ -1545,7 +1545,7 @@ void editor_mode::render_infra_candidates()
 			if (ImGui::IsItemHovered())
 			{
 				state.hovered = i;
-				std::string text{format(STR_C("%s, %s\n%.2f m %s of the axis, %.2f m above the rail top\n%s"), infra::name(candidate.binding.type), anchor.at.track->name().c_str(), std::abs(candidate.offset),
+				std::string text{format(STR_C("%s, %s\n%.2f m %s of the axis, %.2f m above the rail top\n%s"), infra::name(candidate.binding.type), anchor.at.track != nullptr ? anchor.at.track->name().c_str() : "-", std::abs(candidate.offset),
 				                        candidate.offset >= 0.0 ? "right" : "left", anchor.height, candidate.reason.c_str())};
 				if (candidate.reader != nullptr)
 					text += format(STR_C("\nRead by the path %s: event %s, getvalues of the memory cell %s"), candidate.reader->name().c_str(), candidate.event.c_str(), candidate.cell.c_str()) +
diff --git a/application/editormodeprofile.cpp b/application/editormodeprofile.cpp
index 9c23bd56..16c024f2 100644
--- a/application/editormodeprofile.cpp
+++ b/application/editormodeprofile.cpp
@@ -1695,16 +1695,19 @@ void editor_mode::draw_profile_canvas(profile_view const &View, ImDrawList &Draw
 	auto const plotbottom{View.plot_bottom()};
 
 	auto const step{nice_step(View.across * 110.0)};
-	for (auto s = std::ceil((state.view_from + state.origin) / step) * step - state.origin; s <= state.view_to; s += step)
+	auto const firsts{std::ceil((state.view_from + state.origin) / step) * step - state.origin};
+	for (int i = 0; firsts + i * step <= state.view_to; ++i)
 	{
+		auto const s{firsts + i * step};
 		auto const x{View.x_of(s)};
 		Draw.AddLine(ImVec2(x, plottop), ImVec2(x, plotbottom), kGrid);
 		Draw.AddText(ImVec2(x + 3.0f, View.corner.y + 2.0f), kLabel, profile::format_chainage(s + state.origin).c_str());
 	}
 	auto const heightstep{nice_step(View.vertical * 45.0)};
-	for (auto h = std::floor(View.height_of(plotbottom) / heightstep) * heightstep; h <= View.height_of(plottop); h += heightstep)
+	auto const firsth{std::floor(View.height_of(plotbottom) / heightstep) * heightstep};
+	for (int i = 0; firsth + i * heightstep <= View.height_of(plottop); ++i)
 	{
-		auto const y{View.y_of(h)};
+		auto const y{View.y_of(firsth + i * heightstep)};
 		Draw.AddLine(ImVec2(View.corner.x, y), ImVec2(bottomright.x, y), kGrid);
 	}
 	for (auto const &zone : state.context.switches)
@@ -1772,8 +1775,10 @@ void editor_mode::draw_profile_canvas(profile_view const &View, ImDrawList &Draw
 		auto const from{std::max(points.front().chainage, View.chainage_of(View.corner.x))};
 		auto const to{std::min(points.back().chainage, View.chainage_of(bottomright.x))};
 		ImVec2 previous{View.x_of(from), View.y_of(profile::elevation(line, from))};
-		for (auto x = previous.x + 2.0f; x <= View.x_of(to) + 2.0f; x += 2.0f)
+		auto const firstx{previous.x};
+		for (int i = 1; firstx + 2.0f * i <= View.x_of(to) + 2.0f; ++i)
 		{
+			auto const x{firstx + 2.0f * i};
 			auto const chainage{std::min(to, View.chainage_of(x))};
 			ImVec2 const next{View.x_of(chainage), View.y_of(profile::elevation(line, chainage))};
 			Draw.AddLine(previous, next, kGradeLine, 2.5f);
@@ -1827,8 +1832,8 @@ void editor_mode::draw_profile_canvas(profile_view const &View, ImDrawList &Draw
 		plot_label(Draw, ImVec2(at.x + 8.0f, at.y - 22.0f), overlay_color::marked, text);
 	}
 	// heights along the left edge, over everything else
-	for (auto h = std::floor(View.height_of(plotbottom) / heightstep) * heightstep; h <= View.height_of(plottop); h += heightstep)
-		plot_label(Draw, ImVec2(View.corner.x + 4.0f, View.y_of(h) - 8.0f), kLabel, format("%.1f", h));
+	for (int i = 0; firsth + i * heightstep <= View.height_of(plottop); ++i)
+		plot_label(Draw, ImVec2(View.corner.x + 4.0f, View.y_of(firsth + i * heightstep) - 8.0f), kLabel, format("%.1f", firsth + i * heightstep));
 	for (auto const &issue : state.issues)
 	{
 		auto const x{View.x_of(issue.chainage)};
diff --git a/application/editormodeselftest.cpp b/application/editormodeselftest.cpp
index a2281e6c..c44fd133 100644
--- a/application/editormodeselftest.cpp
+++ b/application/editormodeselftest.cpp
@@ -321,8 +321,9 @@ void editor_mode::selftest_step()
 			geometry::bezier const main{track->m_paths[0]};
 			geometry::bezier const other{track->m_paths[1]};
 			std::string text;
-			for (double t = 0.125; t < 1.01; t += 0.125)
+			for (int i = 1; i <= 8; ++i)
 			{
+				auto const t{i * 0.125};
 				auto const point{other.point(t)};
 				double best{std::numeric_limits<double>::max()}, along{0.0};
 				for (int k = 0; k <= 2000; ++k)
@@ -350,8 +351,11 @@ void editor_mode::selftest_step()
 			if (sweep == nullptr)
 				continue;
 			auto const side{sweep->definition().lateral >= 0.0 ? 1 : 0};
-			for (double station = from; station <= to + 1e-9; station += step)
+			if (step <= 0.0)
+				continue;
+			for (int i = 0; from + i * step <= to + 1e-9; ++i)
 			{
+				auto const station{from + i * step};
 				auto const at{sweep->frame_at(station)};
 				WriteLog(format("SELFTEST frame %s %.2f: %.3f %.3f %.3f widening %.4f cant %.4f setback %.4f", name.c_str(), station, at.position.x, at.position.y, at.position.z, at.widening[side], at.cant[side], sweep->setback(at)));
 			}
diff --git a/application/editormodeturntable.cpp b/application/editormodeturntable.cpp
index 4cd20a8f..e6b78d9e 100644
--- a/application/editormodeturntable.cpp
+++ b/application/editormodeturntable.cpp
@@ -402,8 +402,8 @@ bool editor_mode::turntable_fit_end(editor_track::snap_target const &End, turnta
 				for (auto const heading : {line, line + 180.0})
 				{
 					auto const radial{heading_vector(heading)};
-					for (auto radius{static_cast<double>(tool.radius)}; radius >= kMinimumRadius; radius *= 0.9)
-						if (auto const candidate{connect(radial, radius)})
+					for (int i = 0; tool.radius * std::pow(0.9, i) >= kMinimumRadius; ++i)
+						if (auto const candidate{connect(radial, tool.radius * std::pow(0.9, i))})
 						{
 							if (better(*candidate))
 								best = candidate;
@@ -419,8 +419,9 @@ bool editor_mode::turntable_fit_end(editor_track::snap_target const &End, turnta
 		}
 		else
 		{
-			for (auto radius{static_cast<double>(tool.radius)}; radius >= kMinimumRadius && false == best.has_value(); radius *= 0.9)
+			for (int r = 0; tool.radius * std::pow(0.9, r) >= kMinimumRadius && false == best.has_value(); ++r)
 			{
+				auto const radius{tool.radius * std::pow(0.9, r)};
 				auto const gap = [&](double const S) {
 					auto const vertex{e - t * S};
 					auto const radial{vertex - c};
@@ -432,8 +433,9 @@ bool editor_mode::turntable_fit_end(editor_track::snap_target const &End, turnta
 				auto const limit{plan_distance(End.position, centre) + 400.0};
 				double low{0.0};
 				std::optional<double> high;
-				for (double s = 0.25; s <= limit; s += 0.25)
+				for (int i = 1; i * 0.25 <= limit; ++i)
 				{
+					auto const s{i * 0.25};
 					if (gap(s) >= 0.0)
 					{
 						high = s;
diff --git a/editor/editorSpeed.cpp b/editor/editorSpeed.cpp
index bf98e79e..9f4a449e 100644
--- a/editor/editorSpeed.cpp
+++ b/editor/editorSpeed.cpp
@@ -52,8 +52,9 @@ double jerk_limit(double const Curvature, double const Cant, double const Gauge,
 	if (rate(Top) <= Jerk)
 		return Top;
 	double low{0.0};
-	for (double speed = 10.0; speed <= Top; speed += 10.0)
+	for (int i = 1; i * 10.0 <= Top; ++i)
 	{
+		auto const speed{i * 10.0};
 		if (rate(speed) > Jerk)
 		{
 			double high{speed};