Sure! You can add literally any object you like to the collection, that is referenced in the geo nodes modifier settings! 

This is a known bug of Blender 3.6, which will be fixed in 4.0. It has to do with the simulation zone in geo nodes. 

Here is a link to the issue, that's causing the problem:
https://projects.blender.org/blender/blender/issues/111978

For now, what you can do is to bake your simulation nodes before rendering in the "Physics" tab or switch to Blender 4.0, where the bug maybe fixed already.

This is not a loadable addon. These are regular geometry node systems you can append to your scene. 

However you can use the provided asset files to make the product feel like an addon you can access any time! 

Check your normals, they may be inverted. Enable the "Face Orientation" viewport overlay to see the normal direction:

They will only crawl on the blue side of the mesh.

Since blender is currently missing some features, to manipulate animations via geometry nodes, you can offset the animations of the insect instances by doing the following: 

1. Copy the insect you want to use as an instance 
2. Open the side panel in your 3D viewport by pressing "N" on your keyboard
3. Go to "Item" --> "Properties"
4. Change the animation offset and speed to your liking
5. Repeat steps 1-4 until you don't see any animation patterns anymore in the swarm system

Keep in mind, that every one of the copied insects needs to be in the collection you set up in the swarm system to be used for instancing!

Sadly, with Blender's geometry nodes system it is not possible to control animations yet. I will update the product, as soon as there is a way to manipulate animations with geometry nodes! 

1. Open Edit --> Preferences --> File Paths --> Asset Libraries ...and copy the path that you can see in the "Path" textbox
2. Open the file "Insect Swarm Assets.blend" and save it in that direction by clicking on File --> Save As... and insert the path into the top bar 
3. Close all Blender tabs 
4. Open a new Blender scene and open the asset browser
5. Under "Insect Swarm Assets" you should now see all the assets from my product

1. Save the downloaded file on your pc, where you can find it later.
2. Open the blender file in which you would like to import the insect system.
3. File --> Append --> Insect Swarm Assets --> NodeTree --> Insect Swarm_Flying/Crawling/Centipede
4. Add any object to the scene 
5. Add a Geometry Nodes modifier to the object in the modifiers panel and select the Insect Swarm System you want
6. Play with the input attributes in the modifier stack until you like how the swarm behaves.