Go to the location shown in the image below and create the new custom event with a input of integer array. Locations are at the tops of all the screenshots.

Next go to the location shown in the image below and create a new macro called ForLoopWithDelay and copy the image below.

Next go to the location shown in the screenshot below and create the new custom event and the new bool variable and copy the image below. The compile. Make sure you set the event to run on server.

Next go to the function shown in the image below and replace your current nodes with the nodes shown in the image below, you will also need to change the input of the function to a variable instead of an array.

Next using the same custom event you created earlier in the BP_Inventory copy the image shown below.

Next go to the location shown in the image below and replace the current node with the node shown in the image below, you will most likely have to replace a node that has an error. To get the Add New Inventory Slots event call node drag out from the inventory widget variable and search for it.

Next go to the location shown in the screenshot and disconnect and delete the highlighted node shown below.

Next go to the location shown below and add a new function to the interface and name it the same as the image shows.

Then go to the Player Inventory Component and compile it, this may take some time as alot of the project will have to recompile.

Next add the highlighted nodes shown below.

Next go to the location shown in the image below and add the highlighted node.

Next add the is valid shown in the image below.

Next add the highlighted nodes shown below.