Our plug-ins were made for 32-bit and often also 64-bit PhotoShop™ compatible plug-in hosts.
They will work with host applications such as Adobe PhotoShop™ (or Photoshop Elements), JASC or now Corel Paint Shop Pro™, Corel PhotoPaint™ (old), and ULead PhotoImpact™ amongst many others.
There are also excellent free hosts that our plug-ins can be used with, such as IrfanView, XnView, imageN and QFX/LE.