I have been having a hard time with this, any advice?

-Jeff

If you can't get your hip under the uke into the proper position, you have to change to another technique. If you miss uki goshi against a shorter opponent, drop your leg out and go to tai otoshi.

Uki goshi depends on you being able to get your center lower than your opponent's... if not... you have to change techniques. That's not too hard to figure out.

There are some techniques which are just physically, mechanically and practically impossible to apply on shorter/larger people. Trying to fit the technique to all shapes and sizes is a definite recipe for disaster. Just don't.

Your only option is to use a different technique.

Go for Tai-Otoshi if you can't get Uki goshi in.

Sometimes some techniques won't work, that's the truth. No matter how hard you try, it sometimes won't work.

Go for another technique, don't force yourself to do just one technique.

-Taison out

Good points, thanks. I haven't tried using it in randori yet, I just learned the technique the other night. I could only pull it off with 1 out of 3 ukes.

I like Tai-Otoshi too, but can't really do any of my throws against a resisting opponent too well yet. Sometimes I can get a pretty good Osoto-Gari, I think that comes from practicing a lot of rear kicks in karate.
I am hoping to get a lot more practice in over the summer(only 1 night a week right now).