Hi, I'm the author of PneumaticCraft: Repressurized. Just wanted to bring a subtle problem with some of your blocks to your attention...

Non-full-cube blocks (e.g. the Valve Handles) don't override Block#allowsMovement() (isPathfindable() in official mappings). Specifically, this method is intended to determine whether or not an entity can pathfind through the block; the default for land-based and flying entities is to allow pathfinding if the block doesn't have an opaque collision shape. Unfortunately, because the valve handles have a movement-blocking collision box, entities will get stuck (forever) when trying to pathfind through them.

See the screenshot below:

As you can see, the pig is trying (and failing) to pathfind through the valve handle, when it should be going around the wall to get to me. It is a subtle problem which many (most?) modders miss, and generally isn't very noticeable since vanilla entities aren't often around these blocks. However, PneumaticCraft drones often are, and drones getting stuck is a very common source of issues for me :)

Fortunately, it's very easy to fix: simply override allowsMovement() to return false in those blocks of yours which are not a full cube, but do have a movement-blocking collision shape. You will notice that vanilla does this for many of its blocks.

Thanks for reporting this, desht.
Should be resolved in the recent patch