Thanks, the only way i am currently seeing is pretty full of “AdaloApp <-> My Server <-> PingPong” workarounds - and that is obviously pretty inefficient. 
like “getting all user data via API to get the ELEMENT ID” from the specific user from my external server, returning the Element ID to Adalo, make a second request to my server, which is fetching all “weight data” matching the users Element ID and put them into a string (datas seperated with “,”) and than switch to the screen with the graph on it.
I also tried to make a “Bulk-URL” following your Trick: Bulk update records tutorial here. Like “Countdown timer ends → add current list value + last value” on that URL-data-set. but that also doesn’t work (it strangely excludes the first 2 and the last records)