I had to uninstall and reinstall my Designer 9.5 SP1.
After recreating the workspaces I wanted to check one of my process models, but for the receive steps the advanced properties are not shown.
In the Readme for DES_9.5_SP1_Process_Fix11 (which I have installed after the installation) I found the following entry:
WMDPD-8016 (DES_9.5_SP1_Process_Fix10) Advanced properties such as Correlation service and Receive document may not appear for steps of type Receive Task in Language Pack mode. This issue is now resolved.
Strange thing is only, that I did not apply any language packs to this installation.