vRA 6.2 - error while loading a ASD workflow user presentation

Hi,

I have a vRO workflow which I have integrated in vRA as a ASD workflow. The workflow stops at an user interaction. Some of the values in the presentation field are predefined values, that are generated after the workflow starts and loadedi nto the presentation.

When I try to answer the user interaction, the vRA GUI starts to load the fields, but shortly after starting I get the error:

The vRO workflow validation shows no errors, I can run it just fine with the vRO client. When I completely remove the predefined values, the presentation GUI loads the Summary and description fields of the Manual User Interaction, however this end with an error as well after a short time.

2015-12-11 13:40:39,436 vcac: [component="cafe:shell" priority="ERROR" thread="tomcat-http--1278" tenant=""] com.vmware.vcac.shell.ErrorManagerImpl.logToApacheCommons:59 - <92df07b1> Unexpected excepti

on was caught

com.vmware.vcac.platform.framework.error.ErrorCodeException: 504

        at Unknown.gk(Unknown Source)

        at Unknown.pk(Unknown Source)

        at Unknown.Xpc(Unknown Source)

        at Unknown.v2h(Unknown Source)

        at Unknown.LCe(Unknown Source)

        at Unknown.JCe(Unknown Source)

        at Unknown.jzi(Unknown Source)

        at Unknown.mzi(Unknown Source)

        at Unknown.dBi(Unknown Source)

        at Unknown.hBi(Unknown Source)

        at Unknown.aBi/<(Unknown Source)

        at Unknown.p(Unknown Source)

        at Unknown.gadgets.util.makeClosure/<(Unknown Source)

        at Unknown.anonymous(Unknown Source)

Any ideas? Does it have to do with a timeout when loading the presentation?