In the latest update I've added debug messages that will appear in the console. On the PC the console can be accessed by pressing the ~ key twice. (The key to the left of the 1 key) Press the key one more time to close the console.

All the messages related to this Mod will say INFOL_CODEWARNING: Effects: [CPAD_Pointlight_C_#] or [CPAD_PointLightComponent_C BasePlayerChar_C_#]

If you are helping me troubleshoot problems, what you are looking for in the console are any messages that say "Failed", "ERROR", or if more than one Light Scene created for a character.

Regarding performance issues, look for any excessively repeated messages. One of the debug lines to look for is "Request to Update Inventory Called (Count: #)". When first loading the game or any other activity that completely updates the inventory the message will appear and the Cound number will be high, but otherwise it should only appear when moving Power Stone items in the inventory or hotbar and the Count should be much lower, between 1 and 4.

After a "Request to Update Inventory" there should be only one call to "Update Light Visibility"
When toggling the Power Stone items on/off there should be one call to "Update Light Visibility"