I have completed the first part of the chain quest, which required: Sap of Ancient Tree - 5 Medicine with weird Vibes - 40 Malady's Experimental Frog - 40 Squishy Liquid - 40 Nependeath's Honey - 1 I was also able to get the USE item which permanently added HP to my character. However, it seems like you are not able to proceed with the Chain Quest atm, as Mar won't give any quest after completing the first one. Video: Spoiler maybe i'm just doing something wrong and there's another way to proceed with the questline. Bringing this to your attention just incase it is a bug, thanks for reading.
We are aware that the subsequent quests are bugged for some players. We've noted it and will look into it soon.