Andrew,

Don't worry about your English, its a hell of a lot better than my Romanian.

You are asking some very good questions, unfortunately they cover about every
aspect of our arts.

For Tai Sabaki, to begin with, concentrate on better execution of the turns in
your kata.  Keep your center of gravity (your hara) low and work on turning
swiftly.

As far as application of technique, if the words aren't too difficult, try out
what I've listed on my web site www.funkydragon.com/bushi.   Open the section
on Meditations and then click on the icon for Bunkai.  I have a bit of text
about how to apply Kata Seisan. In Shotokan this would be kata Hangetsu (much
of it is identical to the Isshinryu Seisan although with different punches ,
Isshinryu vertical where Shotokan's twisting punches).  It may give you some
ideas.

As for kata practice,  the simplest  answer is to practice as your instructor
shows you.  But work on the small details, where your eye focuses, where your
punch is placed, how you shift as you move between stances.  These things will
help your skill level improve.

Hope this helps, I'll try and work on better answers.

Victor Smith    Bushi No Te Isshinryu           www.funkydragon.com/bushi