Launch WebGUI from SAP Cloud Platform Portal

Hi

we've recently gone live with SAP Portal in SCP giving standard UI5 Apps to the business for approvals (they are on EHP5).

one thing i have been asked to look at it launching WebGUI from SCP Portal.

I have followed the guide here: https://wiki.scn.sap.com/wiki/display/SAPMOB/How+to+Add+a+WebGui+for+HTML+App+to+Fiori?preview=/452566913/452566912/How%20to%20Add%20a%20WebGUI%20for%20HTML%20App%20to%20Fiori%20Launchpad%20Step-by-Step.pdf

however when i try and launch the Portal i get the following error:

i have asked SAP, but they pointed me at the attachment/link above.

All the services are active. i can run the WebGUI from the transaction. I am not seeing any traffic in Network window. i have the role assigned. my connections to gateway work (as i am running other Fiori Apps).

has anyone done this from SCP?