Hi OBK!
I know how you feel - I am on Frame 10 of module 1 with Bristol. Looking back is quite daunting. That's why I don't look back too often!
I have planned to work through each frame, doing the progress tests as I go along. I then plan to go through all the frames again and make notes. If you've been able to do the progress tests then your doing fine - you have the knowledge somewhere in your brain, you now have to devise a revision mechanism to trigger a retrieval. (If your familiar with computer programming, then consider it the same as a 'pointer', i.e. you have to manage it carefully or you lose the data you were referring to).
It's up to you how you make this 'pointer'. Personally, I find bullet point notes useful. I am still hour building at the moment, so what I try to do is incorporate what I have learnt from Bristol in my everyday flying. For example, I couldn’t for the life of me remember the different relationships between aircraft weight types in the weight and balance frame, i.e. Dry Operating mass, Traffic load etc.. so I used MS Word to make a weight and balance sheet/PLOG to use with my hour building. Sure you get a few funny looks when Instructors see you calculating your disposable load in a PA28, but screw those who take the p!ss - it means I am practising it on a regular basis.
I try to do the same with many other subjects i.e. met, flight planning and navigation. If it can't be used (like a lot of the instruments stuff) then I make notes.
I also plan to keep going through the progress tests till I cry with boredom
Good luck, remember there are others in exactly the same boat (or plane). I'm sure you'll be fine.
Bodie