thanks for your tool!
got error on this ifo (using command line)
http://www.64k.it/andres/data/Varie/VTS_02_0.zip
(it's Matrix, DVD PAL)
using this command line ChapterGen.exe -i "d:\matrix\video_ts\VTS_02_0.IFO" -o matrix.txt -f OGG -infps 25.000 -outfps 25.000
error is number 9
translated from italian.. "Index out of bounds" (or similar)
BHH