Okay, -- a short explanation: There are essentially just two types of plugins for a role-playing game (RPG) such as Pillars of Garendall , the "cheat" plugin and the "storyline" plugin.
The cheat frequently allows the player to acquire more money or more health or stronger weapons to make the game easier but does not change the basic game in any way. This is sometimes done by adding a key-stroke event which, for example, just puts 1000 gold pieces into the player's inventory. Since gold is an item which is found in the game itself, removing the plugin from the folder does not remove gold from the player's inventory. If a unique weapon is given to the player, however, the weapon will no longer be there when the plugin is de-activated.
The storyline plugin is closer to a total conversion (TC) for EV Nova. It adds new territories, new characters, new quests, and frequently, new items to the existing story without altering the main story itself. Most often there are rewards for playing through the plugin. Those rewards will still be with the player when the plugin is de-activated unless they are unique creations of the plugin. In other words, the experience gained, the added wealth, etc. are still there as the player continues through the game. The super sword he got will be gone.
I'm sure you probably knew all of that. Now here is where PoG differs from EV Nova. In PoG there is a definite exit point at which time the game is over and the player has done the final quest and cannot return to fight any more battles. Having done that once, most players start a new character and play through again resolving not to go through the final gate, but instead continue to roam the Kingdom of Garendall increasing their experience level, strength, wealth, etc. Storyline plugins add diversions and fun to the whole experience. But questions arise. "Did I find all that the author put there?" "Did I make the best choises?" "Can I beat that beast I ran away from if I am stronger?" So the player may want to play the plugin through several times. In the main game, the "fog of war" prevents the player from seeing areas of the map he has yet to explore. This is true for the first time experience of a plugin as well. However, when the plugin is removed from the folder, the access to new areas is closed but not the "memory" of those areas.
Let me give you a hypothetical example. The player drops a new plugin, Voyage to Valhalla , into his folder. Now when he goes to the Bleeding Forest, he finds a new cave there. This cave transports him to new maps he has never seen before. While exploring this new territory, he finds three "magic apples" which can be used to bribe a witch to let him pass into Valhalla. And so on. "Boy, that was fun. I want to try that again." Remove the plugin from the folder. The cave no longer exists in the Bleeding Forest. Now put the plugin back in the folder. "Ah, there's the cave." Go to what should be unexplored land and find out "We've been here before. Somebody stole the "magic apples" I'm supposed to give to the witch."
There are work-arounds for the plugin developer in Coldstone, but if would be much better if Coldstone allowed the elements of the plugin to completely erase when the plugin was not activated.
I have been verbose. I hope some clarification of my point was evident.