Remove Sparkle.
I made these changes myself, but upstream has also removed Sparkle:
https://github.com/cocoadialog/cocoadialog/issues/81
--- cocoaDialog.xcodeproj/project.pbxproj.orig	2012-05-17 12:52:37.000000000 -0500
+++ cocoaDialog.xcodeproj/project.pbxproj	2019-02-01 12:22:59.000000000 -0600
@@ -12,9 +12,7 @@
 		6190D1D8146CAFB30083364D /* Growl.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = A78A8CE8143784A8007AE363 /* Growl.framework */; };
 		6190D1D9146CAFC20083364D /* Growl.framework in CopyFiles */ = {isa = PBXBuildFile; fileRef = A78A8CE8143784A8007AE363 /* Growl.framework */; };
 		61C9A9D014665F5B0054DD91 /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1058C7A1FEA54F0111CA2CBB /* Cocoa.framework */; };
-		61C9A9D214665F680054DD91 /* Sparkle.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = A78A8D2E1437AC29007AE363 /* Sparkle.framework */; };
 		61C9A9D314665F680054DD91 /* Cocoa.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 1058C7A1FEA54F0111CA2CBB /* Cocoa.framework */; };
-		61C9A9D514665F780054DD91 /* Sparkle.framework in CopyFiles */ = {isa = PBXBuildFile; fileRef = A78A8D2E1437AC29007AE363 /* Sparkle.framework */; };
 		61EC90AC145FACF8003ADF05 /* AppController.h in Headers */ = {isa = PBXBuildFile; fileRef = 61EC906B145FACF8003ADF05 /* AppController.h */; };
 		61EC90AD145FACF8003ADF05 /* AppController.m in Sources */ = {isa = PBXBuildFile; fileRef = 61EC906C145FACF8003ADF05 /* AppController.m */; };
 		61EC90AE145FACF8003ADF05 /* CDCommon.h in Headers */ = {isa = PBXBuildFile; fileRef = 61EC906D145FACF8003ADF05 /* CDCommon.h */; };
@@ -109,7 +107,6 @@
 			dstSubfolderSpec = 10;
 			files = (
 				6190D1D9146CAFC20083364D /* Growl.framework in CopyFiles */,
-				61C9A9D514665F780054DD91 /* Sparkle.framework in CopyFiles */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -199,7 +196,6 @@
 		A78A8CDF14377610007AE363 /* LICENSE */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; path = LICENSE; sourceTree = "<group>"; };
 		A78A8CE8143784A8007AE363 /* Growl.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Growl.framework; path = Frameworks/Growl.framework; sourceTree = "<group>"; };
 		A78A8CF21437938D007AE363 /* CoreFoundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreFoundation.framework; path = System/Library/Frameworks/CoreFoundation.framework; sourceTree = SDKROOT; };
-		A78A8D2E1437AC29007AE363 /* Sparkle.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Sparkle.framework; path = Frameworks/Sparkle.framework; sourceTree = "<group>"; };
 		A7BABA9714456CC800D3F168 /* Foundation.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Foundation.framework; path = System/Library/Frameworks/Foundation.framework; sourceTree = SDKROOT; };
 		A7BABADA1445809700D3F168 /* CoreData.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreData.framework; path = System/Library/Frameworks/CoreData.framework; sourceTree = SDKROOT; };
 		A7BABB051445810000D3F168 /* CoreServices.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = CoreServices.framework; path = System/Library/Frameworks/CoreServices.framework; sourceTree = SDKROOT; };
@@ -214,7 +210,6 @@
 			files = (
 				61C9A9D314665F680054DD91 /* Cocoa.framework in Frameworks */,
 				6190D1D8146CAFB30083364D /* Growl.framework in Frameworks */,
-				61C9A9D214665F680054DD91 /* Sparkle.framework in Frameworks */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};
@@ -286,7 +281,6 @@
 			isa = PBXGroup;
 			children = (
 				A78A8CE8143784A8007AE363 /* Growl.framework */,
-				A78A8D2E1437AC29007AE363 /* Sparkle.framework */,
 				1058C7A0FEA54F0111CA2CBB /* Apple Frameworks */,
 			);
 			name = Frameworks;
@@ -477,7 +471,6 @@
 				8D11072C0486CEB800E47090 /* Sources */,
 				8D11072E0486CEB800E47090 /* Frameworks */,
 				A78A8CEA143784BD007AE363 /* CopyFiles */,
-				A7D4043E153C38E0005FA3CD /* ShellScript */,
 			);
 			buildRules = (
 			);
@@ -555,22 +548,6 @@
 		};
 /* End PBXResourcesBuildPhase section */
 
-/* Begin PBXShellScriptBuildPhase section */
-		A7D4043E153C38E0005FA3CD /* ShellScript */ = {
-			isa = PBXShellScriptBuildPhase;
-			buildActionMask = 2147483647;
-			files = (
-			);
-			inputPaths = (
-			);
-			outputPaths = (
-			);
-			runOnlyForDeploymentPostprocessing = 0;
-			shellPath = /bin/sh;
-			shellScript = "/server/repositories/github/sparkle-release/src/sparkle-release";
-		};
-/* End PBXShellScriptBuildPhase section */
-
 /* Begin PBXSourcesBuildPhase section */
 		8D11072C0486CEB800E47090 /* Sources */ = {
 			isa = PBXSourcesBuildPhase;
--- Resources/en-US.lproj/MainMenu.xib.orig	2012-05-17 12:52:37.000000000 -0500
+++ Resources/en-US.lproj/MainMenu.xib	2019-02-01 13:11:10.000000000 -0600
@@ -45,9 +45,6 @@
 			<object class="NSUserDefaultsController" id="527054022">
 				<bool key="NSSharedInstance">YES</bool>
 			</object>
-			<object class="NSCustomObject" id="987694459">
-				<string key="NSClassName">SUUpdater</string>
-			</object>
 			<object class="NSCustomObject" id="909043032">
 				<string key="NSClassName">AppController</string>
 			</object>
@@ -869,14 +866,6 @@
 					</object>
 					<int key="connectionID">226</int>
 				</object>
-				<object class="IBConnectionRecord">
-					<object class="IBOutletConnection" key="connection">
-						<string key="label">delegate</string>
-						<reference key="source" ref="987694459"/>
-						<reference key="destination" ref="909043032"/>
-					</object>
-					<int key="connectionID">260</int>
-				</object>
 			</array>
 			<object class="IBMutableOrderedSet" key="objectRecords">
 				<array key="orderedObjects">
@@ -1264,11 +1253,6 @@
 						<reference key="parent" ref="0"/>
 						<string key="objectName">AppController</string>
 					</object>
-					<object class="IBObjectRecord">
-						<int key="objectID">252</int>
-						<reference key="object" ref="987694459"/>
-						<reference key="parent" ref="0"/>
-					</object>
 				</array>
 			</object>
 			<dictionary class="NSMutableDictionary" key="flattenedProperties">
--- Resources/Info.plist.orig	2012-05-17 12:52:37.000000000 -0500
+++ Resources/Info.plist	2019-02-01 14:24:36.000000000 -0600
@@ -41,9 +41,5 @@
 	<string>MainMenu</string>
 	<key>NSPrincipalClass</key>
 	<string>NSApplication</string>
-	<key>SUEnableAutomaticChecks</key>
-	<false/>
-	<key>SUPublicDSAKeyFile</key>
-	<string>dsa_pub.pem</string>
 </dict>
 </plist>
--- Source/CDUpdate.m.orig	2012-05-17 12:52:37.000000000 -0500
+++ Source/CDUpdate.m	2019-02-01 12:41:01.000000000 -0600
@@ -34,27 +34,11 @@
 }
 
 - (void) update {
-    SUUpdater * updater = [SUUpdater sharedUpdater];
-    [updater setDelegate:self];
-    NSURL *appcastURL = [NSURL URLWithString:[[[NSBundle mainBundle] infoDictionary] objectForKey:@"SUFeedURL"]];
-    if (appcastURL != nil) {
-        [updater setFeedURL:appcastURL];
+    if ([options hasOpt:@"debug"]) {
+        NSString *output = @"To update, run: sudo port selfupdate && sudo port upgrade CocoaDialog";
+        [self debug:output];
     }
-    else {
-        [updater setFeedURL:[NSURL URLWithString:@"https://raw.github.com/mstratman/cocoadialog/master/sparkle-release/appcast.xml"]];
-    }
-    [updater setSendsSystemProfile:YES];
-    [updater resetUpdateCycle];
-    [updater setAutomaticallyChecksForUpdates:YES];
-    if ([options hasOpt:@"quiet"]) {
-        [updater setAutomaticallyDownloadsUpdates:YES];
-        [updater checkForUpdatesInBackground];
-    }
-    else {
-        [updater setAutomaticallyDownloadsUpdates:NO];
-        [updater checkForUpdates:nil];
-    }
-    [NSApp run];
+    exit(1);
 }
 
 @end