To start, learning when to use R is probably easier than learning when not to use it at first. The main goal with R is that you want to add it at a time when you know it won't cause a fast drop. Fast drops cause bounces which defeats the purpose of using R. You have to consider the action of the L basal insulin (works with either Lantus or Lev) plus the action of the R on top. For today and the next few experiments, you want to learn the onset, nadir and duration of the R so you can safely lay the R action on top of the L action. As a general guideline, the R action shouldn't take more than 100 points off during it's duration. It can be helpful the first few times you use R to coordinate that time with an experienced R user, so they can help you decide if it's a good time to shoot R.
As Sandy said yesterday, you want to avoid the overlap of nadirs of the bolus and basal insulin. Since R typically onsets around +2 and nadirs around +4, we generally avoid shooting early mid cycle. Don't look at Neko's SS as an example of R use, she was non typical for both her R and L onsets and nadirs.
Develop a fail safe method of storing/using your R and L insulins. I used R in a vial and L in cartridges (pens for the US). If shooting at the same time, I always shot L first, then R. Be mindful and in the game. We've seen people mix up the insulins and shoot the L dose of R.

Store them in different parts of the fridge.
Don't use R on the cycle when you increase (which you did today). Those cycles can sometimes have a little extra momentum - as you are seeing. Similarly, don't use R when the bounce is breaking, as those cycles can have extra downward momentum. Both those situations can cause fast drops (ie. more bouncing).
Using R can sometimes have an effect on the following cycle. That's because you've lowered the BG and given the L some good numbers to work with the next cycle. If you ever can't monitor the following cycle, hold off on using R, just in case. Being cautious with R is always a good thing.
You don't always see immediate results from using R. Or it could be that R is just preventing the numbers from getting worse. That's all good. Be patient.
Overtime you will develop an R scale. Take a look at Sandy's
BK's spreadsheet for a great example. He had extreme insulin resistance due to antibodies, so don't let the numbers scare you. My dosing scale was much simpler and I never used more then 0.5 units for numbers over 350. When Neko's dose got lower, the most I gave was 0.1 units. You have to learn what works for Floyd. It's truly ECID.
And finally, using R may be a temporary thing. A cat's situation can change. You may need to just use it for a while until Floyd starts to get used to better numbers. His quick turnaround on the bounce is a good sign.