The effects are documented here.
Foreshadowing :pI'm loath in the extreme to ever suggest that folks write to their Windows Registry with Rainmeter. To each his own of course.
If a user subsequently removes a skin manually or even Rainmeter itself there'd be no way for the skin to revert the application DPI override registry change. It's not mentioned in their FAQ and from some code searches it's unclear if even uninstalling via the project's suggested removal function reverts the change.
For the OP's clarification, the issue is that Rainmeter isn't natively DPI aware. When non-100% scaling is used Windows will naively enlarge all skins by the DPI value, causing blurry looking skins. Only if a skin has been written to include its own custom scaling (most haven't though it has become more common) can the DPI be manually overridden for Rainmeter.exe by the user (see linked thread), or in Droptop's case automatically via a registry change, so that it prevents Windows scaling skins and allows the skins themselves to apply custom scaling if they have it.
However any skins that aren't written to handle their own scaling or haven't detected the Windows DPI value will remain small with that application DPI override setting applied, which presumably is what you're seeing.
Statistics: Posted by Crest — Today, 3:07 am