Okay, I can answer by myself
Looking at the example in the package mentioned above ion my question, there was a slightly issue how I set up the contracts. I just forgot to oz publish
them.
After this, under .openzeppelin/dev-xxx.json
we’ll find not only the contract addresses for Factory and Counter (in my example), but also the address for the app
-contract. This is the final address that needs to get passed into the Factory:
"manifestVersion": "2.2",
"version": "1.0.0",
"app": {
"address": "0xFc2f3B7370FB90f256AA160147F4d7c742F1bB2C"
},
"package": {
"address": "0x58422bec359B909f58BC064E61ea0a86b0d5DC1B"
},
"provider": {
"address": "0x3F235B10b1A670B401f8f63Bb873b98d7EcB646D"
},
Using 0xFc2f3B7370FB90f256AA160147F4d7c742F1bB2C as parameter for the initialize-method in Factory contract in this example helps a lot to make the factory really working