PaintShop Pro is compatible with Photoshop Plugins. Simply install them wherever you please (I use c:\program files\PSPplugins\program name) In PSP, go to file-->preferences-->file locations--->plug-ins and add your plugins folder to the list of locations to utilize. Make sure "enable" and "Use subfolders" are checked. Anything you install in this folder or within a subfolder of it will now be added to the list of available plugins.
When editing, you will find the plugins menu under the effects menu.
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