How to create nav pack?

I've been splitting DVD-9's using Create Ifo by renaming the second half of the VOB's from _01_5 to _01_1 and having IfoEdit create a new Ifo for that set (See ). I have been plagued with crashes and thats why I started doing it this way. The predictable crashes occur when I bring up the "Strip It" and "Split It" windows. But I've come across a couple of VTS sets that cause a crash when I try to correct the nav packs and correct ifo tables of the sets. It's always the second half of the VOB's that causes it. Even when I re-rip these VOB's the same thing happens. The discs burned with this title set will play but trying any nav features on the player causes it to lock up. Any ideas on how to accomplish correcting the pointers another way or what may be causing the crashes in the first place?

Problem found 

Evidently the chapter breaks and VOB split points don't always coincide (does that make sense to anybody?). So if you try to split a large VTS by writing new ifo's for the second half of the VOB's and the first VOB of the second set doesn't start at a the beginning of a chapter there is no nav pack for the first VOB. So, anybody know how I create a nav pack for a VOB? Can I run them through another program (Authoring)?