Yes. Atherosclerosis is independently associated with high total number of LDL particles (ldl-p) and low total number of HDL particles (hdl-p). Cholesterol in particles is actually highly variable, resulting in cases of high ldl-p but low LDL cholesterol (ldl-c), as well as low hdl-p but normal HDL cholesterol (hdl-c). If ldl-c and hdl-c are excellent atherosclerosis still tracks with ldl-p and hdl-p.
They can. Lipids are only one, albeit, important risk factor. Smoking, diabetes, hypertension, genetics, and age are other factors. Since there's nothing that can be done for the last two, excellent control of the first 4 is crucial. (if one is destined to die of a heart attack, better to occur at age 100 than at 40, right?).
Yes, Clarification. Actually, atherosclerosis is not driven by lipids (fat molecules) per-se. Our bodies are mostly water. Fats don’t mix with water. All cells use fat molecules to construct their membranes, separating water inside from water outside. Fats don’t just move around in the water outside cells. All animals manufacture proteins which are water soluble and which carry fat molecules hidden within; see image.