I am looking for temples in Europe where I can go and stay for a month or so. I am not looking for a silent retreat center. What I am looking for is a place I can practice, and take part in the daily workings in a non-silent way, donation based.

They can be Zen or Theravada or something else, although I prefer Zen or Theravada.

Thanks.

I can recommend http://www.cittaviveka.org/ - I stayed there for a week. Email the guest monk and he will answer questions you might have. I met some long term guests there (that stayed for multiple months) so a month stay shouldn't be a problem. 

These links might be of interest:
https://en.wikipedia.org/wiki/List_of_Buddhist_temples#Europe
Theravada Buddhist Communities Europe

I once spent a couple of weeks at their Amaravati branch. Same idea, I guess.