i've been using heat n bond lite for years- the difference is (steam a seam you use steam to fuse it) heat N bond you use a dry iron.
i've also used it with many batiks and have never had the (stain) problem mentioned above...i did have a problem once when i used an iron that was way too hot & i kept it on the fabric way too long-
the issue that was described above with the batik could easily have been caused by the wax in the fabric not being completely washed away- sometimes you will get a batik that still has a waxy feel to it- those unless you pre-wash in hot water-remove the excess wax can cause some problems using any fusable. i'd say her problem was a problem with the fabric not with the fusable product being used.