Sorry to head you're experiencing troubles! In general there is no known incompatibility of the spine-unity runtime with Pixel Perfect Camera rendering, at least none that we could reproduce so far.
Did you check whether a normal Sprite (a non-Spine Sprite, a normal image dragged into the scene resulting in a Sprite Renderer GameObject) renders correctly when moved around? If this is not the case, then the problem lies outside of your skeleton asset.
roomyrooms ：
PS: My PPU is set to 32 and I have the spine skeleton scale set to (1/32). Not sure why 1x scale is huge, actually, since my base atlas image is 1:1 pixel size, and my scales in spine are all 1x (this is unique to spine-unity- 1x scale in pixi's runtime is accurate to the atlas image).
The actual displayed size depends on your camera settings as well (mostly the Pixel Perfect Camera component Inspector settings, especially whether Run in Edit Mode is enabled) and also a bit on your Game View settings (the aspect ratio / resolution). Unfortunately there are many settings that can lead to incorrect preview or rendering with Pixel Perfect Camera, some can be seen e.g. at the start of this tutorial video.
Other problems could be having an exported atlas texture not being a power of two and having the Texture import settings Advanced - Non-Power of two set to anything but none, attachments not being of scale 1 (which you said is the case) or having them located at fractional positions or rotated.
If your problems still persist after checking the potential causes listed above, could you please send us a minimal Unity project that still shows this issue? You can send it as a zip package to contact@esotericsoftware.com, briefly mentioning this forum URL so that we know the context. Then we can have a look at what's going wrong.
