Lith Printing - Pre-rinsing to remove incorporated developers from paper?

If by Agfa MCC you mean Adox MCC 110 (rebranding?) then I've had good luck with it. You do need a pretty substantial amount of sodium sulfite to tame the pepper fog, but I think it liths quite well. It gets really gritty and yields some minor color changes. The color changes are much stronger with second development lith, though fade a lot with fixing.

Pretty risky for me to have an electrical warming tray in my bathroom but found a cordless one that might work. I also found after using Moersch easy lith is that I only use TR 4 fix. No acid stop that really helps keeping the midtones that it and rapid fix use to take away. Using Agfa MCC111 & Zone VI VCII paper. The latter really does well with a golden brown colour. Post some when it's dry. Zone VII paper