Pull up ExtensionInterface.

Assets/Cryville/Crtr/Browsing/ExtensionInterface.cs

@@ -0,0 +1,9 @@
+using System;
+using System.Collections.Generic;
+
+namespace Cryville.Crtr.Browsing {
+	public abstract class ExtensionInterface {
+		public abstract IEnumerable<ResourceConverter> GetResourceConverters();
+		public abstract IEnumerable<LocalResourceFinder> GetResourceFinders();
+	}
+}

Assets/Cryville/Crtr/Browsing/ExtensionInterface.cs.meta

@@ -0,0 +1,11 @@
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+MonoImporter:
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+  defaultReferences: []
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Assets/Cryville/Crtr/Browsing/LegacyResourceManager.cs

@@ -25,13 +25,26 @@ namespace Cryville.Crtr.Browsing {
 		static LegacyResourceManager() {
 			foreach (var asm in AppDomain.CurrentDomain.GetAssemblies()) {
 				foreach (var type in asm.GetTypes()) {
-					if (type.IsSubclassOf(typeof(ResourceConverter))) {
-						var converter = (ResourceConverter)Activator.CreateInstance(type);
-						foreach (var f in converter.GetSupportedFormats()) {
+					if (!type.IsSubclassOf(typeof(ExtensionInterface))) continue;
+					var ext = (ExtensionInterface)Activator.CreateInstance(type);
+					try {
+						var cs = ext.GetResourceConverters();
+						if (cs != null) {
+							foreach (var c in cs) {
+								var fs = c.GetSupportedFormats();
+								if (fs == null) continue;
+								foreach (var f in fs) {
+									if (f == null) continue;
 							if (!converters.ContainsKey(f))
-								converters.Add(f, new List<ResourceConverter> { converter });
-							else converters[f].Add(converter);
+										converters.Add(f, new List<ResourceConverter> { c });
+									else converters[f].Add(c);
+								}
+							}
 						}
+						Logger.Log("main", 1, "Resource", "Loaded extension {0}", ReflectionHelper.GetNamespaceQualifiedName(type));
+						}
+					catch (Exception ex) {
+						Logger.Log("main", 4, "Resource", "Failed to initialize extension {0}: {1}", ReflectionHelper.GetNamespaceQualifiedName(type), ex);
 					}
 				}
 			}

Assets/Cryville/Crtr/Extensions/Extensions.cs

@@ -0,0 +1,27 @@
+using Cryville.Crtr.Browsing;
+using Cryville.Crtr.Extensions.Bestdori;
+using Cryville.Crtr.Extensions.Malody;
+using Cryville.Crtr.Extensions.osu;
+using Cryville.Crtr.Extensions.Quaver;
+using System.Collections.Generic;
+
+namespace Cryville.Crtr.Extensions {
+	public class Extensions : ExtensionInterface {
+		public override IEnumerable<ResourceConverter> GetResourceConverters() {
+			return new ResourceConverter[] {
+				new BestdoriChartConverter(),
+				new MalodyChartConverter(),
+				new osuChartConverter(),
+				new QuaverChartConverter(),
+			};
+		}
+
+		public override IEnumerable<LocalResourceFinder> GetResourceFinders() {
+			return new LocalResourceFinder[] {
+				new MalodyChartFinder(),
+				new osuChartFinder(),
+				new QuaverChartFinder(),
+			};
+		}
+	}
+}

Assets/Cryville/Crtr/Extensions/Extensions.cs.meta

@@ -0,0 +1,11 @@
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