Finally a WF that will not give you any 'Package Load' error on VS.NET 2005 Release version launch. I have just downloaded and installed it on my VM.
I will be posting more about my experiments with WF later on, for now you can download here and play with it yourself .
It seems that the first installation was not all that smooth and things had to be reinstalled to get everything working. Although there were not 'Package Load' Failures, this time the development environment would become unstable on the launch of certian workflow console applications. Having said that a complete re-install of WF did the trick for me and I have been successfully able to develop, run and test workflows over the weekend.