diff --git a/installwizard.cpp b/installwizard.cpp
index fe0ae1e..349880e 100644
--- a/installwizard.cpp
+++ b/installwizard.cpp
@@ -45,7 +45,7 @@ InstallWizard::InstallWizard(QWidget *parent, Settings *settings) :
     setButtonLayout(layout);
 
     ui->setupUi(this);
-    connect(cancelButton, &QPushButton::clicked, this, &InstallWizard::cancel);
+    connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));
 
     setPage(Page_Setup, new InstallWizard_Setup(this, settings));
     setPage(Page_Eula, new InstallWizard_Eula(this));
diff --git a/installwizard_copy.cpp b/installwizard_copy.cpp
index 8017224..8208ff0 100644
--- a/installwizard_copy.cpp
+++ b/installwizard_copy.cpp
@@ -62,12 +62,12 @@ void InstallWizard_Copy::initializePage()
     qRegisterMetaType<QList<FileOperation> >("QList<FileOperation>");
     copyWorker = new FileCopyWorker(((InstallWizard *)wizard())->getFileCopyOperations());
     copyWorker->moveToThread(&copyThread);
-    connect(&copyThread, &QThread::finished, copyWorker, &QObject::deleteLater);
-    connect(this, &InstallWizard_Copy::copy, copyWorker, &FileCopyWorker::copy);
-    connect(copyWorker, &FileCopyWorker::fileChanged, this, &InstallWizard_Copy::setCopyFilename);
-    connect(copyWorker, &FileCopyWorker::progressChanged, this, &InstallWizard_Copy::setCopyProgress);
-    connect(copyWorker, &FileCopyWorker::errorMessage, this, &InstallWizard_Copy::setCopyErrorMessage);
-    connect(copyWorker, &FileCopyWorker::copyFinished, this, &InstallWizard_Copy::finishCopy);
+    connect(&copyThread, SIGNAL(finished()), copyWorker, SLOT(deleteLater()));
+    connect(this, SIGNAL(copy()), copyWorker, SLOT(copy()));
+    connect(copyWorker, SIGNAL(fileChanged(const QString)), this, SLOT(setCopyFilename(const QString)));
+    connect(copyWorker, SIGNAL(progressChanged(qint64,qint64)), this, SLOT(setCopyProgress(qint64,qint64)));
+    connect(copyWorker, SIGNAL(errorMessage(const QString)), this, SLOT(setCopyErrorMessage(const QString)));
+    connect(copyWorker, SIGNAL(copyFinished(QList<FileOperation>)), this, SLOT(finishCopy(QList<FileOperation>)));
     copyThread.start();
 
     emit copy();
diff --git a/installwizard_patch.cpp b/installwizard_patch.cpp
index 90bde16..a0043f8 100644
--- a/installwizard_patch.cpp
+++ b/installwizard_patch.cpp
@@ -66,9 +66,9 @@ void InstallWizard_Patch::initializePage()
 #endif
 
     networkReply = nam.get(networkRequest);
-    connect(networkReply, &QNetworkReply::readyRead, this, &InstallWizard_Patch::downloadRead);
-    connect(networkReply, &QNetworkReply::downloadProgress, this, &InstallWizard_Patch::updateProgress);
-    connect(networkReply, &QNetworkReply::finished, this, &InstallWizard_Patch::downloadFinished);
+    connect(networkReply, SIGNAL(readyRead()), this, SLOT(downloadRead()));
+    connect(networkReply, SIGNAL(downloadProgress(qint64,qint64)), this, SLOT(updateProgress(qint64,qint64)));
+    connect(networkReply, SIGNAL(finished()), this, SLOT(downloadFinished()));
 }
 
 void InstallWizard_Patch::cleanupPage()
@@ -141,12 +141,12 @@ void InstallWizard_Patch::downloadFinished()
     qRegisterMetaType<QList<FileOperation> >("QList<FileOperation>");
     extractWorker = new FileExtractWorker(patchFile->fileName(), filesToExtract);
     extractWorker->moveToThread(&extractThread);
-    connect(&extractThread, &QThread::finished, extractWorker, &QObject::deleteLater);
-    connect(this, &InstallWizard_Patch::extract, extractWorker, &FileExtractWorker::extract);
-    connect(extractWorker, &FileExtractWorker::fileChanged, this, &InstallWizard_Patch::setExtractFilename);
-    connect(extractWorker, &FileExtractWorker::progressChanged, this, &InstallWizard_Patch::updateProgress);
-    connect(extractWorker, &FileExtractWorker::errorMessage, this, &InstallWizard_Patch::setErrorMessage);
-    connect(extractWorker, &FileExtractWorker::finished, this, &InstallWizard_Patch::finishExtract);
+    connect(&extractThread, SIGNAL(finished()), extractWorker, SLOT(deleteLater()));
+    connect(this, SIGNAL(extract()), extractWorker, SLOT(extract()));
+    connect(extractWorker, SIGNAL(fileChanged(const QString)), this, SLOT(setExtractFilename(const QString)));
+    connect(extractWorker, SIGNAL(progressChanged(qint64,qint64)), this, SLOT(updateProgress(qint64,qint64)));
+    connect(extractWorker, SIGNAL(errorMessage(const QString)), this, SLOT(setErrorMessage(const QString)));
+    connect(extractWorker, SIGNAL(finished(QList<FileOperation>)), this, SLOT(finishExtract(QList<FileOperation>)));
     extractThread.start();
     emit extract();
 }
diff --git a/installwizard_setup.cpp b/installwizard_setup.cpp
index 94451ef..186abfe 100644
--- a/installwizard_setup.cpp
+++ b/installwizard_setup.cpp
@@ -122,7 +122,7 @@ bool InstallWizard_Setup::validatePage()
 
     if (ui->stackPages->currentIndex() == Page_Install)
     {
-        QDir dir(ui->cbInstallSource->currentData().toString());
+        QDir dir(ui->cbInstallSource->currentText());
 
         if (!dir.exists())
         {
@@ -135,7 +135,7 @@ bool InstallWizard_Setup::validatePage()
 
         // Copy page will copy baseq3/pak0.pk3.
         iw->clearFileCopyOperations();
-        iw->addFileCopyOperation(ui->cbInstallSource->currentData().toString() + QString("/QUAKE3/baseq3/pak0.pk3"), ui->txtInstallDest->text() + QString("/baseq3/pak0.pk3"));
+        iw->addFileCopyOperation(ui->cbInstallSource->currentText() + QString("/QUAKE3/baseq3/pak0.pk3"), ui->txtInstallDest->text() + QString("/baseq3/pak0.pk3"));
         iw->setQuakePath(ui->txtInstallDest->text());
     }
     else if (ui->stackPages->currentIndex() == Page_InstallSteam)
@@ -214,7 +214,7 @@ bool InstallWizard_Setup::isComplete() const
 {
     if (ui->stackPages->currentIndex() == Page_Install)
     {
-        return !ui->cbInstallSource->currentData().toString().isEmpty() && !ui->txtInstallDest->text().isEmpty();
+        return !ui->cbInstallSource->currentText().isEmpty() && !ui->txtInstallDest->text().isEmpty();
     }
     else if (ui->stackPages->currentIndex() == Page_InstallSteam)
     {
@@ -288,7 +288,7 @@ void InstallWizard_Setup::on_txtLocatePath_textChanged(const QString & /*arg1*/)
 
 void InstallWizard_Setup::on_btnInstallBrowseSource_clicked()
 {
-    const QString location = QFileDialog::getExistingDirectory(wizard(), "Select Quake III Arena CD-ROM directory", ui->cbInstallSource->currentData().toString());
+    const QString location = QFileDialog::getExistingDirectory(wizard(), "Select Quake III Arena CD-ROM directory", ui->cbInstallSource->currentText());
 
     if (!location.isEmpty())
     {
diff --git a/minizip/ioapi.h b/minizip/ioapi.h
index 2a94e09..b6556b5 100644
--- a/minizip/ioapi.h
+++ b/minizip/ioapi.h
@@ -42,7 +42,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
-#include <QtZlib/zlib.h>
+#include <zlib.h>
 
 #if defined(USE_FILE32API)
 #define fopen64 fopen
diff --git a/minizip/unzip.c b/minizip/unzip.c
index 9fa03c0..8afe46a 100644
--- a/minizip/unzip.c
+++ b/minizip/unzip.c
@@ -72,7 +72,7 @@
         #define NOUNCRYPT
 #endif
 
-#include <QtZlib/zlib.h>
+#include <zlib.h>
 #include "unzip.h"
 
 #ifdef STDC
diff --git a/minizip/unzip.h b/minizip/unzip.h
index 4c819b5..b965c46 100644
--- a/minizip/unzip.h
+++ b/minizip/unzip.h
@@ -48,7 +48,7 @@ extern "C" {
 #endif
 
 #ifndef _ZLIB_H
-#include <QtZlib/zlib.h>
+#include <zlib.h>
 #endif
 
 #ifndef  _ZLIBIOAPI_H