I just purchased CDP to test, and it is a really nice app, but without support for Germany, I'm not sure if it'll make sense for me to use it. The number of trade shows and card shops is growing rapidly throughout Germany. I'm excited to see that this is currently under review. If you need people to test the implementation, I'm sure everyone here would be more than happy to help.

Germany is the leading TCG market in Europe, accounting for nearly 27% of the EU’s total revenue and the highest transaction volume on Cardmarket. By not supporting German sellers, you are missing out on the primary hub of European card commerce and thousands of potential professional power-users.