I'm trying to deploy the Nintex My Workflow Tasks web part to many identically structured sites. Each site is in its own unique site collection (one root web per site collection). Using powershell I create the site collection with the Nintex web part feature activated, based on my own custom WSP. I have tried two methods to script the web part:

1. Created a webpart page that contains the My Workflow Tasks. I have saved that to a central library and import it into the new site. The web part does not display on the page

2. Edited the web part (to suit my own requirements - changed title, columns displayed, etc), exported it to a DWP file, and then called the WebPartManager via Powershell to import the dwp and add it to an existing page. I get the message Unable to import web part.

Has anyone any ideas how I can script this so the Web Part (with my edits) is included on the same page in every site?