diff --git a/deps/ox/src/ox/std/stringliteral.hpp b/deps/ox/src/ox/std/stringliteral.hpp
index f78b946..adf4127 100644
--- a/deps/ox/src/ox/std/stringliteral.hpp
+++ b/deps/ox/src/ox/std/stringliteral.hpp
@@ -19,7 +19,7 @@ namespace ox {
  */
 class StringLiteral: public detail::BaseStringView {
 	public:
-		consteval StringLiteral() noexcept = default;
+		constexpr StringLiteral() noexcept = default;
 
 		constexpr StringLiteral(StringLiteral const &sv) noexcept = default;
 
diff --git a/release-notes.md b/release-notes.md
index 43a2a13..41b4281 100644
--- a/release-notes.md
+++ b/release-notes.md
@@ -1,3 +1,9 @@
+# d2025.07.0
+
+* Add sub-command for exporting TileSheets as PNG files.
+* Add 'Reload Project' menu item under File.
+* Fix opening a project to mark an unopenable file as closed in the config file on startup.
+
 # d2025.06.0
 
 * Add ability to remember recent projects in config
diff --git a/src/nostalgia/modules/gfx/include/nostalgia/gfx/consts.hpp b/src/nostalgia/modules/gfx/include/nostalgia/gfx/consts.hpp
index 887c7cc..1b4bfe0 100644
--- a/src/nostalgia/modules/gfx/include/nostalgia/gfx/consts.hpp
+++ b/src/nostalgia/modules/gfx/include/nostalgia/gfx/consts.hpp
@@ -21,9 +21,28 @@ constexpr ox::Array<ox::StringLiteral, 2> FileExts_TileSheet{
 	FileExt_ng,
 };
 
+constexpr ox::Array<ox::StringLiteral, 2> FileExts_Palette{
+	FileExt_npal,
+};
+
 [[nodiscard]]
 constexpr bool isTileSheet(ox::StringViewCR path) noexcept {
-	return endsWith(path, FileExt_nts) || endsWith(path, FileExt_ng);
+	return ox::any_of(
+		FileExts_TileSheet.begin(),
+		FileExts_TileSheet.end(),
+		[path](ox::StringLiteral const &ext) {
+			return endsWith(path, ext);
+		});
+}
+
+[[nodiscard]]
+constexpr bool isPalette(ox::StringViewCR path) noexcept {
+	return ox::any_of(
+		FileExts_Palette.begin(),
+		FileExts_Palette.end(),
+		[path](ox::StringLiteral const &ext) {
+			return endsWith(path, ext);
+		});
 }
 
 }
diff --git a/src/olympic/keel/include/keel/assetmanager.hpp b/src/olympic/keel/include/keel/assetmanager.hpp
index 62cda92..2719e45 100644
--- a/src/olympic/keel/include/keel/assetmanager.hpp
+++ b/src/olympic/keel/include/keel/assetmanager.hpp
@@ -64,11 +64,13 @@ class AssetContainer {
 
 	protected:
 		constexpr void incRefs() const noexcept {
+			oxAssert(m_references < ox::MaxValue<decltype(m_references)>, "reference count exceeds maximum");
 			++m_references;
 		}
 
 		constexpr void decRefs() const noexcept {
 			--m_references;
+			oxAssert(m_references >= 0, "negative references");
 		}
 
 		[[nodiscard]]
@@ -162,6 +164,7 @@ template<typename T>
 constexpr AssetRef<T>::AssetRef(AssetContainer<T> const*c) noexcept: m_ctr(c) {
 	if (m_ctr) {
 		m_ctr->updated.connect(this, &AssetRef::emitUpdated);
+		m_ctr->incRefs();
 	}
 }