The interim system is only currently valid for those students who were on it prior to whatever date in Nov 2008 it officially ceased. From that date no-one else was allowed to start an interim course. One or two schools are applying for an extension to this, but it will be properly dead real soon, thank goodness. We've wasted enough time with 737s.
The questions you refer to were all credited, as were the ones on TCAS II (only one helicopter with it, and that experimental). I believe there was a total of 7. For the record, you need to know the inner workings of the IRS (i.e. know of the existence of ring laser gyros) but not the excruciating detail, so ignore the question banks. EFIS and a bit of FMS are all fair game, though.
Also, for the record, there will be no changes in regulations, new syllabuses etc until at least the end of 2009. In any case, it is unlikely that the average student will even notice.
Phil