Photomorphis Photoshop Brushes are only compatible with Photoshop or Photoshop Elements. Please refer to the individual product descriptions for specific software version requirements.
That said, many of the stamp brush collections include 5000 pixel versions of the stamp brush patterns. If you want to, you can just open any of these larger 5000 pixel JPEG images in Photoshop, ON1, Topaz Texture Effects, (or any other software that allows the creative use of layers) and load it into a new layer over the image. Change its blend mode to multiply (or you can play with the other blend modes to get various looks) and it will be like using a large stamp brush. As a layer, you'll be able to scale it, adjust its opacity, etc.
If you decide to go this route, please confirm that the collection you're interested in contains JPEG files with the brushes. You can find this info on the product description page.