No, your ABS light shouldn'd be on all the time. Probably bad wiring to one of the hubs. Mine was bad going to my driverside-front and I'll probably get around to fixing it eventually. Check the wiring for fraying, etc. at the hubs. Hopefully that'll take care of it.
Same-same with my O/D Off indicator. I'm hoping it's just the wiring to the O/D switch on the shifter. Unfortunately, yours is likely more serious since you're having problems with tranny itself. Swapping the tranny should fix it though, good luck with your replacement find.
And if of course all else fails, check the diagnostic charts Cre posted. Personally I tend to leave those as last resorts, but to each their own.
