I was having trouble calling SharpSvn from within an Activity. One of the major errors was getting "Execution of the workflow failed. Reason: Mixed mode assembly us built against version 'v2.0.50727' of the runtime and cannot be loaded in
the 4.0 runtime without additional configuration information."
I fixed this by modifying all the .exe.config files in the trident install so that their <startup> element also had the attribute useLegacyV2RuntimeActivationPolicy="true".
This fixed the issue. Not sure if it will have repercussions down the line. Wasn't sure which one was causing the problem, and I'll look at doing some more work to narrow it down later.
I haven't found any problems with this change, I'll report if I do.