No problems, you got it right. The Kirin kit is incorrectly labelled, although at the time they DID think they labelled it correctly. The basic difference is that the T-72BM had the K-5 ERA and new Glacis plate and the T-90 basically added the shtora emitters.
There are other issues with the Kirin kit, with it having been based on early 1990's information. It was a cool kit at the time, but is now very inaccurate. I built this kit as well, I thought it was the best thing around at the time. Also, you did a VERY good job with it, better than my build.
Just think, now that you know the T-72BM is not ht ebest, you can build ANOTHER tank for its cargo! Lucky you!