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That looks like yellow/mustard algae to me, though it could be pollen. If it's yellow/mustard algae, then it will tend to grow in shady areas of the pool, including on the walls and it will act like dust but will feel slimy. If it's pollen, then it will tend to settle to the bottom in areas where circulation has things settle and will feel squishy. Looking at a sample under a microscope is pretty definitive since pollen is solid and often spiky and round while the algae is often oblong and semi-transparent where you can see the interior.

Yellow/mustard algae is more resistant to chlorine and most certainly your 2 ppm FC with 100 ppm CYA isn't even enough to prevent green algae let alone yellow/mustard algae. I suspect you are using Trichlor tabs/pucks that got your CYA that high -- it could even be higher than 100 ppm. You need to get your own good test kit, the Taylor K-2006 you can get here if you do not have one.

I would first of all dilute your pool water to lower your CYA level since it's hard to manage a pool at such a high CYA level since it requires rather high FC levels to prevent algae growth and even higher levels to shock the pool to get rid of such algae permanently.

Let's say you get your CYA lower to 50-60 ppm. Then, you would need to supershock the pool to around 30 ppm using chlorinating liquid or bleach you add slowly over a return flow at the deep end with the pump running. You maintain this high level until 2-3 days after the algae is no longer visible. You also need to get behind light niches and under removable ladders to expose the algae that is likely there as well (remember it likes shade and such areas don't get good circulation of chlorine) and you need to put into the pool everything that gets into it -- poles, nets, brushes, pool toys, etc. so that you don't reintroduce the algae later on. You also need to wash your swimsuits thoroughly with soapy water.

Once you get rid of this algae, then you can maintain normal chlorine levels according to Ben's Best Guess CYA chart where you will note that the minimum FC is 8 ppm for a CYA of 100 ppm -- instead you'll likely have 50 ppm CYA so a minimum FC of at least 3 ppm at all times.