CDS should only contain chlorine dioxide gas (CLO2) in distilled water. So, it should not make any difference which activator you use, except 4% HCL won't produce more than about 2500 PPM when using the 12 ml + 12 ml recipe. That is why I came up with the double infusion method using 5 ml of MMS + 5 ml of 4% HCL (twice) which will produce 3000 ppm when double infused into the same distilled water.
The only way some activator might get into the CDS is if you spill some of the reactor solution into the receiver solution, the distilled water turned into CDS.
Test strips don't have much resolution and only give an approximate idea of the CLO2 concentration. It is important when testing to use distilled water to dilute the CDS, otherwise you will probably get inaccurate readings.
Regarding dosing, start low and work up to what you can tolerate. That can take a week or longer.
You can test Xylitol to see if it reduces CLO2 concentration by measuring a CDS dose in water and then add some Xylitol and test again.
I have been taking CDS by holding it in my mouth over a crowned molar that is bothering me, trying to kill any infection. Mixed some DMSO with the CDS to help drive the CLO2 deeper. Tomorrow I see my dentist and I suspect he will remove the crown and look under it. Not looking forward to that.