Re: Dragon Age 2 DLCs - Steam/Origin
@kartondoosI had a similar issue when attempting to run DAII on my steam deck, and it turned out to be due to a lack of specific required drivers. which I have noticed tends to be the issue with installing older games like this on any system.
First, Go On Nividia and download "NVIDIA PHYSX SYSTEM SOFTWARE 9.16.0318" Install this according to the instructions.
Next, you want to go into Dragon Age II's install folder, for me it's C:\Program Files (x86)\Origin Games\Dragon Age II but if you have it through Steam it may be in your Steamapps folder instead. Click on the __Installer folder, then the directx folder, and finally redist folder. Here you should find an exe called DXSETUP. Run this and install it.
At this point try running the game again, if the issue was that you didn't have the proper drivers it should now run.