A collegue created a SP2010 workflow in visio, and imported it into SharePoint Designer 2010.
His flow used the following actions:
SharePoint Designer 2010 throws an error when he validates the workflow (check for errors) or tried to deploy it.
The error (for searchablility):
This workflow action is not supported in this region of the workflow.
It can only be inserted in certain types of blocks.
SharePoint Designer does not show the actions as available.
After a bit of searching we found that these actions can only be added when inserted in an Impersonation Step.
This is logical as the impersonation step runs as the author of the document, in stead of the workflow starter.
Hope this is helpful.
Implemented AkismetExtension on the blog a week ago, and it seems to be working.
Lets hope it lasts.