IMHO the advantages of PicMaster, which seems to be a competent image editor, is its small footprint on your hard disk, and the ability to use Photoshop plugins, & there are LOTS of those plugins available. The disadvantages are it lacks layers, and some may dislike the somewhat dated appearance of the GUI. For more serious editing, which requires layers, there's The GIMP, or some might want to check out the free Chasys Draw IES -- jpchacha.com/index.php
PicMaster installs in the Program Files (x86) folder, with an additional folder in Users\ [UserName]\ AppData\ Roaming\. On the 1st run after activating / registering PicMaster an empty folder was added in Users\ [UserName]\ AppData\ Local\ VirtualStore\ Program Files (x86)\ PicMaster\. During installation I recorded these changes to the registry: New keys: 39769, New values: 105650, Changed values: 36, Total changes: 145455. Often with that many entries most new keys have a common heading, e.g., Drivers, making it possible to search from the end of the text file to the last Driver key in that case, so I can review the entries from then on. That was Not the case with PicMaster, so all I can say for sure is that there's one new PicMaster key + one new key for uninstall.