using ISEG as datasource for cycle counting BW cube

ISEG captures the cycle count transactions in R3. As far as I know there is no business content cycle counting cube or extractors. I would like to create an extractor against ISEG to bring into BW in order to create a custom BW cycle counting cube. I would like to know any pertinant notes on advice in general on using ISEG as a datasource. I do understand how to create new extractors; I'm looking for any nuances with ISEG. Perhaps data quality, keys, delta processing, new content etc., just for examples.

thanks

Bob Bechtel