Your hardware supplier should be able to help you. If not, in the US, you can purchase an annual support contract. I assume Germany has the same offering. You can also purchas single-issue tickets on the CODESYS store. Or, you can purchase "The Book of CODESYS" which is a good resource for getting up to speed on CODESYS.
If you have remote access to the CODESYS directory on the device, you could download your own .app and .crc files, update the bootproject in the .cfg file, then start the runtime. It should start your downloaded project.