A few drills with a knife. Start with the knife in hand. Just roll with it and don’t cut yourself. next roll with the knife held with both hands and stay safe. After that roll as you cut a person on the ground or standing /moving do the cut inside the roll wheather you are rolling over or next to it and don’t show the knife to the public. It’s a tool not a flag. To roll better throw a knife up and catch it on the way down and roll with it using it’s movement in a joining sort of way. Practice this a bit and than have a friend throw the knife for you. Roll to retrieve the knife on the ground and remember not to give of yourself to get an advantage over the other. You will get killed and no one liles a rich grave digger.
Learning from chance. Many times we change our routine without concious thought. You do A before B or use the other hand and so on. If you pay attention it will pay back (horrible pun but hay I like it) Your body and sometimes your brain (the nerves extend to the entire body and it evolves as much as you use it wisely) tell you that there is a better way or that one drill should be different.  I for one prefer the set movement before the improve ones. It works better for me. Check what works for you. Know yourself.
a little thing about the aligned squat. We put a lot of emphesis on relaxing the spine and the thigh muscles but as Mikhail pointed we are a complete system (yea I know Echo echo) Try to do a few complete slow squats and each time focus on relaxing another part. The ankles, shins, knees, thighs, the position of the head, the shoulders and don’t forget the way your toes are spread or clenched on the ground.  Have fun and remember sweat takes away toxins from your body so it’s a good thing. If you are too hygenic than you will have a slow weak immune system. Same as hitting and any other field.
I read a lot on this field and others. A nice article I read yesterday mentioned a wise advice. A big part of keeping healthy is to avoid the bad stuff. For example too much drinking and smoking. Doing bad exercise of no relaxation work afterwards (holding on to the tension built).  Many people train to exhustion, run to their limit and so on. They sleep so little they yawn all day and later expect the body to perform well into old age or in a real trial when it has been destroyed and depleted over years.  Take a look at yourself and see if you are doing anything such as pumping up a bicep to look good or doing some exercise till it hurts and feeling the burn. It creates an imbalance and as we are a complete system we will pay for it one day or today. 
After a long day of walking with a load or just a day in the office on a bad chair it is good to open the back. Try this: Either with a towel draped over a sturdy door or a good pull up bar, suspend yourself and move according to your breath. A 30 breath per hand hold is a good starting point and it will relax and release tightiness in your torso arms and lower body if you allow the body to unwind from the point of hold. Enjoy.
A bit on rolling and eyes. As you roll, look all the time so there is no part where you see nothing. If you have a partner look at him/her and also see what is around. Try these rolling variations and see how these affect the sight. Roll very swiftly but keep the roll short. Meaning you cover very little distance but fast and see how this affects your vision. Jump up a few times and one the last drop straight into a roll without any upwards bounce. Roll while putting two fingers jently on the sides of your nose. Make something up and if you feel like it write me about it.  Enjoy your creativity and remember your character is your destiny not my bad spelling 🙂
Holding your breath and relaxation. Apart from being able to relax under a choke it can also be used to help you become aware of your body and when one system is in nead the rest line up to form the best energy savings alignement for you. Consider this: Stand naturally and start to sway from side to side and breath count with the sways. Start with 2 for each phase Inhale pause Exhale pause. Now sway forward and backwards and also diagonally (left heel to right toe axis) Once 2 is easy raise the count and see how you relax and align the body under this condition you put yourself in. It is the purpose that matters. A push up is a push up. The meaning makes it different. Oh and don’t rise too fast. Be logical.

Simple. Stand far enough of each other to be out of range for limbs and held tools. Now walk naturally and glance on the point where you are comfortable to hit and keep walking out of that range in the same pace. This will teach you placement and distance well and later on add the knife and go for the unseen stab or other hit. A pro does not show his knife not in the hand and not later on. See the big picture.

Another drill; Lie on the ground and have a partner stand close and try to step into you. The point is to stomp into the body (incave a lung for example) and your job is to move at the last minute out of the way but to stay close to the legs so you can work and stop the other from kicking. Change places and see how this works for you. The one standing needs to to maintain his composure and not overstep. Simply walk and breathe on the person (if he fails to get out of the way) and don’t secrifice your posture of composure to gain any of his. It is a road leading downstairs.

lower yourself to one knee next to your friend on the ground. Take a sharp branch or a knife or whatever you choose and start to slowly push the tip into the body and face of your firend. Make it real so he learns otherwise you are doing both a disservice. The one on the gorund has to feel which part of the body has to move and where. Imagine the tip deviding the body into several parts. It is a pivot point and decide by using your senses and mind which part is best pivoted. For example a stab to the shoulder blade will not be helped by a roll to the right or left if the tip is on the inside of the bone. you can however roll forward and glide the tip on the body so you are maybe cut but not punctured. See what works for you. 

A nice drill for distance and placement. Start by standing in front of each other. Gather the picture in your head and close your eyes. Now tell each other in turn to reach over with a limb and touch the other in a specific place. For example: Right knee to the partners left knee, left fist to parallel side shoulder socket. As you become comfortable try two and more and you can advance to light strikes as you go. Change placement or even do it while walking and so on. Have fun.

One of the best things in the Ryabko way of teaching is the lack of insturction. By getting things done your way you truely get to know yourself and by getting only principle and tasks you find your way without any copy catting. That is my view and my lesson learned by getting to ask the right questions for myself and by given ways to test my honesty.  (for example the simple stand up and lie down. There are infinite variation, do 100 and don’t repeat anything, it will show you much more than rolling for half an hour each day the same way. )

here: go to the ground with no padding. A stone floor will do. Start to move along with your breath and don’t stop for 10 minutes. Don’t feel sorry for yourself if you think this gets hard. Don’t be surprised if you feel more than bodily things during and after. The first time we jump we are not brave. The second one …