During setup while trying to decompile I get an Gradle error GRADLE_BUILD FAILED [-23]
The console output:
g400178@bw22502-lnx:~/Downloads/MCreator 1.8.1 [1.12.2] Mac-Linux 32-64bit$ /usr/java/jre1.8.0_191/bin/java -jar mcreator.jar
[Thu Dec 20 10:35:29 CET 2018] [Launcher] Java version: 1.8.0_191, specification: 1.8
[Thu Dec 20 10:35:29 CET 2018] [Launcher] Current JAVA_HOME for running instance: /usr/java/jre1.8.0_191
[Thu Dec 20 10:35:29 CET 2018] [Launcher] Installation path: /home/g400178/Downloads/MCreator 1.8.1 [1.12.2] Mac-Linux 32-64bit
[Thu Dec 20 10:35:29 CET 2018] [Launcher] User home of MCreator: /home/g400178/.mcreator/
[Thu Dec 20 10:35:30 CET 2018] [WebIO] Reading from URL: https://mcreator.net/app
[Thu Dec 20 10:35:30 CET 2018] javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1946)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:316)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.Handshaker.fatalSE(Handshaker.java:310)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1639)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.ClientHandshaker.processMessage(ClientHandshaker.java:223)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.Handshaker.processLoop(Handshaker.java:1037)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.Handshaker.process_record(Handshaker.java:965)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.SSLSocketImpl.readRecord(SSLSocketImpl.java:1064)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.SSLSocketImpl.performInitialHandshake(SSLSocketImpl.java:1367)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1395)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.SSLSocketImpl.startHandshake(SSLSocketImpl.java:1379)
[Thu Dec 20 10:35:30 CET 2018] at sun.net.www.protocol.https.HttpsClient.afterConnect(HttpsClient.java:559)
[Thu Dec 20 10:35:30 CET 2018] at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractD…
[Thu Dec 20 10:35:30 CET 2018] at sun.net.www.protocol.https.HttpsURLConnectionImpl.connect(HttpsURLConnectionImp…
[Thu Dec 20 10:35:30 CET 2018] at co.pylo.mcreator.j.a.a(Unknown Source)
[Thu Dec 20 10:35:30 CET 2018] at co.pylo.mcreator.j.b.a.a(Unknown Source)
[Thu Dec 20 10:35:30 CET 2018] at co.pylo.mcreator.a.<init>(Unknown Source)
[Thu Dec 20 10:35:30 CET 2018] at co.pylo.mcreator.Launcher.lambda$main$1(Unknown Source)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventQueue.access$500(EventQueue.java:97)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventQueue$3.run(EventQueue.java:709)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventQueue$3.run(EventQueue.java:703)
[Thu Dec 20 10:35:30 CET 2018] at java.security.AccessController.doPrivileged(Native Method)
[Thu Dec 20 10:35:30 CET 2018] at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
[Thu Dec 20 10:35:30 CET 2018] at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
[Thu Dec 20 10:35:30 CET 2018] Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
[Thu Dec 20 10:35:30 CET 2018] at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:397)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.validator.Validator.validate(Validator.java:262)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1621)
[Thu Dec 20 10:35:30 CET 2018] ... 28 more
[Thu Dec 20 10:35:30 CET 2018] Caused by: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
[Thu Dec 20 10:35:30 CET 2018] at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
[Thu Dec 20 10:35:30 CET 2018] at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
[Thu Dec 20 10:35:30 CET 2018] at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:392)
[Thu Dec 20 10:35:30 CET 2018] ... 34 more
[Thu Dec 20 10:35:31 CET 2018] Failed to load import format classes! Things won't go right!
[Thu Dec 20 10:35:31 CET 2018] java.io.FileNotFoundException: /home/g400178/.mcreator/source/1.12.2-source.jar (No such file or directory)
[Thu Dec 20 10:35:31 CET 2018] at java.util.zip.ZipFile.open(Native Method)
[Thu Dec 20 10:35:31 CET 2018] at java.util.zip.ZipFile.<init>(ZipFile.java:225)
[Thu Dec 20 10:35:31 CET 2018] at java.util.zip.ZipFile.<init>(ZipFile.java:155)
[Thu Dec 20 10:35:31 CET 2018] at java.util.zip.ZipFile.<init>(ZipFile.java:169)
[Thu Dec 20 10:35:31 CET 2018] at co.pylo.mcreator.java.c.a(Unknown Source)
[Thu Dec 20 10:35:31 CET 2018] at co.pylo.mcreator.java.c.<init>(Unknown Source)
[Thu Dec 20 10:35:31 CET 2018] at co.pylo.mcreator.java.b.<init>(Unknown Source)
[Thu Dec 20 10:35:31 CET 2018] at co.pylo.mcreator.a.<init>(Unknown Source)
[Thu Dec 20 10:35:31 CET 2018] at co.pylo.mcreator.Launcher.lambda$main$1(Unknown Source)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:311)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventQueue.access$500(EventQueue.java:97)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventQueue$3.run(EventQueue.java:709)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventQueue$3.run(EventQueue.java:703)
[Thu Dec 20 10:35:31 CET 2018] at java.security.AccessController.doPrivileged(Native Method)
[Thu Dec 20 10:35:31 CET 2018] at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:74)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:205)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
[Thu Dec 20 10:35:31 CET 2018] at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
[Thu Dec 20 10:35:31 CET 2018] Pylo sync status: false
[Thu Dec 20 10:35:31 CET 2018] MCreator setup process started ...
[Thu Dec 20 10:35:31 CET 2018] [Setup] Path for MDK zip: /tmp/minecraftforge294137566627043120mdk
[Thu Dec 20 10:35:42 CET 2018] [GA] Tracking page: /1.8.1/launch
[Thu Dec 20 10:36:01 CET 2018] [Workspace FS] Storing workspace to the file system
[Thu Dec 20 10:39:00 CET 2018] [Workspace FS] Storing workspace to the file system
[Thu Dec 20 10:39:00 CET 2018] [GA] Tracking page: /1.8.1/close
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