Application Builder on 18.4

I recently updated to release 18.4, from the 18.3, two of our dev server.
On both servers when I try to create a new application with Application Builder I get an error (see the screenshot) and the creation is aborted.
Below a part of the tomcat log.

Can you help me to understand what can be the issue and what I can do to solve it?

Thanks!

2018-11-21 11:27:40.759 INFO [main] org.apache.catalina.startup.Catalina.start Server startup in 173164 ms

2018-11-21 11:28:26.164 INFO [http-nio-8080-exec-7] com.metaparadigm.jsonrpc.JSONRPCBridge.registerLocalArgResolver registered local arg resolver com.metaparadigm.jsonrpc.HttpServletRequestArgResolver for local class javax.servlet.http.HttpServletRequest with context javax.servlet.http.HttpServletRequest
2018-11-21 11:28:26.164 INFO [http-nio-8080-exec-7] com.metaparadigm.jsonrpc.JSONRPCBridge.registerLocalArgResolver registered local arg resolver com.metaparadigm.jsonrpc.HttpSessionArgResolver for local class javax.servlet.http.HttpSession with context javax.servlet.http.HttpServletRequest
2018-11-21 11:28:26.164 INFO [http-nio-8080-exec-7] com.metaparadigm.jsonrpc.JSONRPCBridge.registerLocalArgResolver registered local arg resolver com.metaparadigm.jsonrpc.JSONRPCBridgeServletArgResolver for local class com.metaparadigm.jsonrpc.JSONRPCBridge with context javax.servlet.http.HttpServletRequest
2018-11-21 11:28:27.702 INFO [http-nio-8080-exec-3] com.sun.jersey.server.impl.application.WebApplicationImpl._initiate Initiating Jersey application, version 'Jersey: 1.19 02/11/2015 03:25 AM'
2018-11-21 11:29:01,664 [Appian Work Item - 0 - process-design] WARN com.appiancorp.common.ObjectSynchronizer - 4 services were missing types.
2018-11-21 11:29:32.621 INFO [http-nio-8080-exec-2] com.sun.jersey.server.impl.application.WebApplicationImpl._initiate Initiating Jersey application, version 'Jersey: 1.19 02/11/2015 03:25 AM'
2018-11-21 11:30:36.650 INFO [http-nio-8080-exec-8] org.apache.catalina.core.StandardWrapperValve.invoke 2018-11-21 11:30:34,647 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failure importing object: content[_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40536] cause: com.appiancorp.ix.ConsumerException: type=content, srcId=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40536, dstId=7008, cause=com.appian.data.client.AdsException: APNX-3-0000-008: Unable to process the request: org.apache.http.conn.HttpHostConnectException: Connect to localhost:5404 [localhost/127.0.0.1] failed: Connection refused: connect, level=ERROR, object=ContentHaul[content=[Content:id=null,name=STM2_SupTicketDetails,type=32,subtype=6,uuid=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40536,parent=7001],resourceName=<null>,roleMap=com.appiancorp.suiteapi.content.ContentRoleMap@63b9b3c2[
ContentRole[name=readers,inherit=true,allowForAll=false]
ContentRole[name=authors,inherit=true,allowForAll=false]
ContentRole[name=administrators,inherit=true,allowForAll=false]
ContentRole[name=denyReaders,inherit=false,allowForAll=false]
ContentRole[name=denyAuthors,inherit=false,allowForAll=false]
ContentRole[name=denyAdministrators,inherit=false,allowForAll=false]
securityVector=15:SEC_PUBLIC=true,SEC_CREATOR_ADMIN=false,SEC_INH_ADMIN=true,SEC_INH_EDITOR=true,SEC_INH_VIEWER=true,SEC_ALL_ADMIN=false,SEC_ALL_EDITOR=false,SEC_ALL_VIEWER=false
]]
2018-11-21 11:30:34,647 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failure importing object: content[_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40540] cause: com.appiancorp.ix.ConsumerException: type=content, srcId=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40540, dstId=7009, cause=com.appian.data.client.AdsException: APNX-3-0000-008: Unable to process the request: org.apache.http.conn.HttpHostConnectException: Connect to localhost:5404 [localhost/127.0.0.1] failed: Connection refused: connect, level=ERROR, object=ContentHaul[content=[Content:id=null,name=STM2_CreateUpdateSupTicket,type=32,subtype=6,uuid=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40540,parent=7001],resourceName=<null>,roleMap=com.appiancorp.suiteapi.content.ContentRoleMap@4dd0206d[
ContentRole[name=readers,inherit=true,allowForAll=false]
ContentRole[name=authors,inherit=true,allowForAll=false]
ContentRole[name=administrators,inherit=true,allowForAll=false]
ContentRole[name=denyReaders,inherit=false,allowForAll=false]
ContentRole[name=denyAuthors,inherit=false,allowForAll=false]
ContentRole[name=denyAdministrators,inherit=false,allowForAll=false]
securityVector=15:SEC_PUBLIC=true,SEC_CREATOR_ADMIN=false,SEC_INH_ADMIN=true,SEC_INH_EDITOR=true,SEC_INH_VIEWER=true,SEC_ALL_ADMIN=false,SEC_ALL_EDITOR=false,SEC_ALL_VIEWER=false
]]
2018-11-21 11:30:34,649 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failure importing object: content[_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40532] cause: com.appiancorp.ix.ConsumerException: type=content, srcId=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40532, dstId=7007, cause=com.appian.data.client.AdsException: APNX-3-0000-008: Unable to process the request: org.apache.http.conn.HttpHostConnectException: Connect to localhost:5404 [localhost/127.0.0.1] failed: Connection refused: connect, level=ERROR, object=ContentHaul[content=[Content:id=null,name=STM2_DeleteSupTicketEntry,type=32,subtype=6,uuid=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40532,parent=7001],resourceName=<null>,roleMap=com.appiancorp.suiteapi.content.ContentRoleMap@36ace1b2[
ContentRole[name=readers,inherit=true,allowForAll=false]
ContentRole[name=authors,inherit=true,allowForAll=false]
ContentRole[name=administrators,inherit=true,allowForAll=false]
ContentRole[name=denyReaders,inherit=false,allowForAll=false]
ContentRole[name=denyAuthors,inherit=false,allowForAll=false]
ContentRole[name=denyAdministrators,inherit=false,allowForAll=false]
securityVector=15:SEC_PUBLIC=true,SEC_CREATOR_ADMIN=false,SEC_INH_ADMIN=true,SEC_INH_EDITOR=true,SEC_INH_VIEWER=true,SEC_ALL_ADMIN=false,SEC_ALL_EDITOR=false,SEC_ALL_VIEWER=false
]]
2018-11-21 11:30:34,649 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failure importing object: content[_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40544] cause: com.appiancorp.ix.ConsumerException: type=content, srcId=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40544, dstId=7010, cause=com.appian.data.client.AdsException: APNX-3-0000-008: Unable to process the request: org.apache.http.conn.HttpHostConnectException: Connect to localhost:5404 [localhost/127.0.0.1] failed: Connection refused: connect, level=ERROR, object=ContentHaul[content=[Content:id=null,name=STM2_SupTicketDashboard,type=32,subtype=6,uuid=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40544,parent=7001],resourceName=<null>,roleMap=com.appiancorp.suiteapi.content.ContentRoleMap@1f3164bc[
ContentRole[name=readers,inherit=true,allowForAll=false]
ContentRole[name=authors,inherit=true,allowForAll=false]
ContentRole[name=administrators,inherit=true,allowForAll=false]
ContentRole[name=denyReaders,inherit=false,allowForAll=false]
ContentRole[name=denyAuthors,inherit=false,allowForAll=false]
ContentRole[name=denyAdministrators,inherit=false,allowForAll=false]
securityVector=15:SEC_PUBLIC=true,SEC_CREATOR_ADMIN=false,SEC_INH_ADMIN=true,SEC_INH_EDITOR=true,SEC_INH_VIEWER=true,SEC_ALL_ADMIN=false,SEC_ALL_EDITOR=false,SEC_ALL_VIEWER=false
]]
2018-11-21 11:30:34,650 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failure importing object: content[_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40548] cause: com.appiancorp.ix.ConsumerException: type=content, srcId=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40548, dstId=7011, cause=com.appian.data.client.AdsException: APNX-3-0000-008: Unable to process the request: org.apache.http.conn.HttpHostConnectException: Connect to localhost:5404 [localhost/127.0.0.1] failed: Connection refused: connect, level=ERROR, object=ContentHaul[content=[Content:id=null,name=STM2_UserRecordLink,type=32,subtype=6,uuid=_a-0000e1b2-1538-8000-6a03-01ef9001ef90_40548,parent=7001],resourceName=<null>,roleMap=com.appiancorp.suiteapi.content.ContentRoleMap@6530a6c4[
ContentRole[name=readers,inherit=true,allowForAll=false]
ContentRole[name=authors,inherit=true,allowForAll=false]
ContentRole[name=administrators,inherit=true,allowForAll=false]
ContentRole[name=denyReaders,inherit=false,allowForAll=false]
ContentRole[name=denyAuthors,inherit=false,allowForAll=false]
ContentRole[name=denyAdministrators,inherit=false,allowForAll=false]
securityVector=15:SEC_PUBLIC=true,SEC_CREATOR_ADMIN=false,SEC_INH_ADMIN=true,SEC_INH_EDITOR=true,SEC_INH_VIEWER=true,SEC_ALL_ADMIN=false,SEC_ALL_EDITOR=false,SEC_ALL_VIEWER=false
]]
2018-11-21 11:30:34,650 [http-nio-8080-exec-8] ERROR com.appiancorp.object.quickapps.QuickAppObjectType - Failed to successfully create Quick App on operation 'import from templates' - rolling back
java.lang.IllegalStateException: We cannot have any import failures
at com.appiancorp.object.quickapps.operations.shared.ImportTemplatesOperation.invoke(ImportTemplatesOperation.java:123)
at com.appiancorp.object.quickapps.QuickAppObjectType.runOperations(QuickAppObjectType.java:164)
at com.appiancorp.object.quickapps.QuickAppObjectType.createQuickApp(QuickAppObjectType.java:87)
at com.appiancorp.object.quickapps.QuickAppObjectType.save(QuickAppObjectType.java:67)
at com.appiancorp.object.quickapps.QuickAppObjectType.save(QuickAppObjectType.java:32)
at com.appiancorp.object.action.create.CreateActionHandler.handleSave(CreateActionHandler.java:131)

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