When you say the Explorer won't load, is it the Internet Explorer? Did you create the java keystore? Did you download the Client.zip and create copy the Options.properties into the unzip client?
AppWorx 9.3 BroadCom change the way the client is distributed. In the past, the Client is initiated from a browser. Once initiated, the client is download into your pc/laptop then started.
In 9.3 the Apache Webiste only distributes the Client.zip file. If you are using Java 8 update that is earlier than update 18X. You don't have to create a keystore. If you are using a later Java, you have to either create a keystore, or edit he java.policy file in lib/security to enable anon and self-sign certs.
https://techdocs.broadcom.com/us/en/ca-enterprise-software/intelligent-automation/applications-manager/9-3/Installation_Guide/Applications_Manager_Installation_Advanced_Topics/Using_Custom_SSL_Certificates_for_Connection_Authentication.html