The 1.3 and 1.4 patches for the base game were "mostly" playable (before that, anything even remotely resembling WWII was purely accidental), but offhand I don't recall anything about rising Dissent. I'd check the press laws and other law settings to see if one of them isn't causing the increase, and check the ministers for any traits that could cause the issue. Spies might also be able to cause Dissent in the base game, but I don't remember if that's true or not, so you might need to use counter-espionage to remove any enemy spies operating within your country.
If possible, pick up the Semper Fi expansion and download the official patches for it, which should bring you up to where you can actually complete a campaign without things breaking the game more often than not. For the Motherland and Their Finest Hour add several nice features, but they're nowhere near as essential as the first expansion (and its final patch), which fixed several major game-breaking issues.