Always happy to be corrected.
For me a Kulturzentrum has always been a "Veranstaltungsort für kulturelle Aktivitäten" (=arts centre), as in oreg's first quote, and if it's more than that, which jas says a lot of them are, then we need to think of a sensible equivalent.
An arts centre, at least in the UK, is "a functional community centre with a specific remit to encourage arts practice and to provide facilities such as theatre space, gallery space, venues for musical performance, workshop areas, educational facilities, technical equipment etc.", and as such I would have thought that this covers the second of oreg's definitions (i.e. leaning towards a community centre).
Until now, I'd never heard of an "interpretive centre". Having done some research, they would seem to be a modern innovation. All well and good. But even so, I concur with oreg that they are museums, and _not_ necessarily culturally biased. An interpretive centre is a centre that interprets facts (of whatever kind) for the general public, and I still wouldn't say that this is necessarily a Kulturzentrum. Sometimes yes, but not always.
"The Interpretive Centre is dedicated to fostering public awareness and knowledge of the inherent values of wetland ecosystems throughout North America, and to marshaling public support for their conservation. The goal is to make learning about wetlands FUN!"http://www.cabottrail.com/whales/
"Welcome to the Pleasant Bay Whale Interpretive Centre, Nova Scotia's newest, innovative attraction which inspires, promotes and preserves an awareness of whales and marine life in Cape Breton"
Jas, if a Kulturzentrum can be the above, then yes, by all means, let's leave the entry standing as it is. But I still contest that "arts centre" should be added.