Ethol stopped printing the replenishment instructions years ago. I have the sheet with exact way to do it in one of my notebooks. I shall look for them and scan them for you tomorrow if you will let me have an email address at
jaykhill@aol.com.
IIRC, the powdered form of LPD only can be used as a replenished developer; not the liquid. I can tell you that I used a gallon of working solution so long that one could not see the print in the developer. But the stuff never stained and seemed to stay very constant. Great stuff.