We are specialised in ERP->PDM->CAD integration through our Enterprise software DataSuite. This provides high level of flexibility through built in ETL platform and rules engine. So you can basically define your workflow the way you want it and this can solve your second question as well as DataSuite can read the data from different sources and transform it according to your business rules. The workflow can be fully automated via triggers (e.g. PDM Approved or check-in etc.) so all the integration can be done on a server in background.
Please send me a private message if you need more information.