Agile Toolkit as a framework for PHP

Agile Toolkit as a framework for PHP

Im trying to improve as a programmer, im learning the basics and im at the
stage where i can design a full database driven website with various
complicated features. Saying that i am still very much a beginner that
learned by needing to do something and google at each step i got stuck at.
I currently expanded from php and mysql to learning PDO and OOP which im
still getting to grips with.
I thought it was too soon to go into a framework until i got a better
understanding of OOP but when i seen Agile Toolkit
http://agiletoolkit.org/ i fell in love. Those UI things are what slow me
down most as i dont know much Jquery and keep me from learning more coding
so it makes a lot of sense to learn this.
Not knowing a lot about frameworks other than the basic concept of MVC and
it been a bunch of classes and guidelines, i was wondering if using a
framework limits me, if i find a jquery or even a non jquery solution for
an issue im trying to solve, is it easy to implement it along with my
framework stuff? Also same question with php, if i have a class i use for
solving a problem that agile toolkit doesnt have can i integrate it with
my framework, i assume ill have to update things in the class like
database queries etc to conform with the framework but can i use the php
functions and other stuff or would it be a complete re-write to make it
compatible, is a framework almost like a separate language if that is the
case.
Before i make the jump into all the tutorials i wanted to see if anyone
had any feedback, also whats peoples opinions on the framework, it seems
to not get that much mention or have a lot of people asking questions on
it so i was wondering if it was too early to get involved with it. For
instance its not a keyword here which is a bit worrying if i have a
problem