I also struggle with weakening questions by a large margin vs other question types. The way I view it is the following:

I've gotten to the point where even if I don't clearly see the argument in LR, for question types besides weaken and RRE, I can use intuition or process of elimination to identify the correct answer. These questions require you to take one step towards finding the right answer. You find the flaw and circle the answer that matches what you found. This is helpful because if you can't find the flaw, you can work backwards from the answers.

But for weakening, you have to understand the flaw before you can begin thinking about what may magnify that flaw. It is tough to work backwards with these questions because there are multiple identification steps.

I've found that my inability to master weakening questions is related to my inability to truly identify the flaw in every argument. While working on this has mostly helped for weakening questions, it's also helped in most other question types.

This may be unique to me, but I hope this helps!

@ are we allowed to use it anytime or only during the 10-minute break?

I'm not sure what specific test this began, but the later tests seem to have more challenging LR sections.