Developing PCI for TAO platform

Hi, I am a developer for CITO. We are in the midst of developing a PCI for the TAO platform. I noticed there are some discrepancies the TAO standard. I would love to make an '1EdTech standard' PCI and am torn in between implementing the creator part. For our planning I need to have a basic PCI working in a short amount of time. I followed this guide: https://github.com/oat-sa/taohub-articles/blob/master/forge/pci-development.md for PCI development I got TAO (in docker) running and registered the PCI to reload. I am unable to get the Portable element compilation working: https://github.com/oat-sa/taohub-articles/blob/master/forge/pci-development.md#portable-element-compilation

Has anyone have experience with PCI compilation for TAO and know where to find this task ?

grunt portableelement -e=qtiItemPci -i=likertScaleInteraction

There is a grunt file in the following folder ( tao/views/build ) , but no task portablelement.

Another question: In some other example PCIs (from numworkx or vretta) I noticed they make use of an Iframe and hosting the interaction external, is this common practice? What does the standard say about this?

Thanks in advance, patrick.deklein@cito.nl