V1 supports:

• Blender 3.0 - 3.6.5
• Auto-Rig Pro 3.68.12 - 3.68.83

V2 supports:

• Blender 4.0+
• Auto-Rig Pro 3.69.10+

You receive both versions with your purchase.

Because all the rigs have been setup with export to a game engine (Unreal/Unity) in mind. A frame rate of 30fps is the standard for game animation.

Only the Complete Version of the rig library includes animations with the rigs.
Also make sure you're using Blender 3.0 or up, and Auto-Rig Pro 3.68.12 or up.

You need to open the Action Editor in Blender and there you can select the animations (aka actions) in the dropdown menu. By default the 'CharacterName_default' action is active.

Unzip the zipfile that you download from Blender Market and follow the Install Notes.

You can also follow this video tutorial.

Please have a look at this YouTube tutorial I made.

Stretchy arms/legs are turned off by default in order for the rigs to be game engine compatible. 

But these are the steps to turn on stretchy arms/legs:

• Stretchy FK arms/legs
  Pose Mode > select the hand/foot controller > Tool tab > adjust the Stretch Length (FK) value.
  
  
• Stretchy IK arms/legs
  Pose Mode > select the hand/foot controller > Tool tab > adjust the Stretch Length (IK) value.
  
  Alternatively, you can turn on the Auto Stretch property. When you move the hand/foot IK controller, the arm/leg will automatically stretch.

1. Allosaur - walk
2. Apatosaurus - walk
3. Bear - walk
4. Bird - fly
5. Cat - walk
6. Crab - walk
7. Dog - run
8. Dolphin - swim
9. Dragon - fly
10. Duck - walk
11. Elephant - walk
12. Giraffe - walk
13. Gorilla - walk
14. Horse - gallop
15. Human - walk, run
16. Kangaroo - jump
17. Lizard - walk
18. Mouse - run
19. Ostrich - run
20. Pig - trot
21. Shark - swim
22. Snake - slither
23. Spider - walk
24. Turtle - walk

Please have a look at this workflow video tutorial.

Make sure to turn on the Fake User shield for all the actions of a rig.
When you don't turn on Fake User for the actions, it can happen that Blender will remove them when re-opening the .blend file.

It can be used as a reference for the placement of bones within your own model, and also acts as a visual guide when scaling the rig.
But it is safe to delete if you don't need it.

You probably had Auto Keying on when you scaled the rig, thus creating scale keyframes.
Be sure to turn off Auto Keying when scaling a rig.

Auto-Rig Pro add-on > Edit Reference Bones > select a bone in the desired chain > Limb Options > change the amount of bones > Match To Rig

Note that when you change the bones to a HIGHER amount, those extra bones won't contain any keyframes/animation.

This happens when you change the amount of bones in a limb to a SMALLER amount of bones. The channels of the bones that have been removed will give an error in the Graph Editor. You can simply select all these channels and delete them.

Auto-Rig Pro add-on > Edit Reference Bones > select a bone in the desired chain > Disable > Match To Rig

Auto-Rig Pro add-on > Edit Reference Bones > select a limb from the Add Limb dropdown > Match To Rig

The Giraffe, Dragon and Horse rigs all have custom clavicle bones.

Please have a look at this video tutorial.

First of all, for both methods make sure that in the Outliner your model is placed within the root collection of your rig.

• Appending (creating a copy of the rig):
  File > Append > browse to the rig file on your computer and double-click it > Collection > select the root collection of the rig (the one with only the name of the rig, so NOT the collections rigname_cs and rigname_grp_rig) > Append.
  
  

• Linking (creating a reference to the rig source file):
  - File > Link > browse to the rig file on your computer and double-click it > Collection > select the root collection of the rig (the one with only the name of the rig, so NOT the collections rigname_cs and rigname_grp_rig) > Link
  - Object Mode > Object > Relations > Make Library Override
  - Note that you can’t edit a linked rig. You will need to do that in the rig source file.

Please be aware that in Blender a rig can reference only one action. So when you bring in a rig (through appending or linking) that contains multiple animations,  it will only contain the action that is active in the original rig file.

Because Blender can't find its textures.
Go to File > External Data > Find Missing Files > navigate to the textures folder