A save file from someone else might have glitches if you have a mod installed that changes the balance. Especially if the skill tree has been modified. I don't have any such mods. I have a mod installed that allows you to play all campaigns in version 3.0. But it shouldn't affect the campaigns in the expansion pack, as it uses a different save file for the vanilla game and the expansion pack.
Added 8 minutes later
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OTE=Boris K;199419]Or install patch 3.1. Where can I get this patch?