That folder path is more reserved for Studio One system files and typically get removed during new Studio One updates.What works best for me is to create custom presets while in Studio One using the following steps.

1. Click here (see arrow) and select "Store Preset".
2. Give it a name and description.
3. Select an existing subfolder or type in a custom sub-folder name and press OK.



Once created, Studio One saves them to tha appropriate instrument folder:

I don't think it is a good idea to put this stuff on the C drive.
Because it inflates that drive and you should be backing that drive up.
Where do you store your songs?
On my system I have many drives and have allocated drive J for PreSonus stuff.
There is a folder on that drive called J:\PreSonus
In that folder the songs, templates and presets are stored.. It is automatically updated..
Within J:\Presonus\Presets, Studio One will create a sub folder called PreSonus and within that, folders like Mai Tai or Fat Channel etc .
When you create your own folder as the previous post explains, this is where you can find them. You can even move them around or create new folders using explorer etc but remember to right click in the browser and refresh.

Typing in a sub-folder name worked - thanks!