PDF markup tool

WE are only able to open PDF's in read only and not able to markup the files via PW Share/Web. We are hosting our own ProjectWise. 

I think ProjectWise needs to be federated which we are not able to federate. 
- Our dmskrnl.cfg file has STS=1, we have setup user as Security type = Federated Identity but when we login to PW using Bentley IMS account, it says 'cannot login to datasource"
Anyone seen this issue and can help us to resolve? 

Also, does WSG server need to be public facing server even though we are hosting the PW and all users interested in  PDF markup are internal ?