They released a new patch, thus why it won't work.
Based on the loose files supplied it includes support for the Zodiak Tournament DLC (Not yet released, should be out within days I guess.) and also prototype movies for two other larger DLC, Transport Terror and Chinese New Year.
However since the game archives are kept together most of the game gets updated once a DLC is released or near release if they decide to provide the files earlier.
Probably it's combined with other general game fixes and improvements but it does mean a 2 - 3 GB download every time it happens. (This new content format works a bit better since the data changed in total is around 8 GB.)
I have all the DLC--unfortunately*--and they work just fine with the 2.0 trainer, with one exception: Nightmare in North Point. That seems to need to run from a fresh instance through Steam and the Weak Enemies option is, at best, highly unstable.
*I'd highly recommend skipping the Top Dog Silver, Top Dog Gold, and Red Envelope DLC. The first 2 add experience and the 3rd adds money. None are worth a cent, let alone 2-3$ apiece.
[Edited by XaosetErikson, 1/19/2013 1:29:55 AM]
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